You are on the right way...but the more precise would be "I need to ASSESS the position" (and not "understand" the position).
In other words you'll need to use your positional knowledge to decide which side (White or Black) is better and why. Position you set is a good one, because you can make your mind in short time, that no immediate tactics wins material.
Positional knowledge is made of many elements:  weaknesses, developpement, space advantage, pawn structure and so on.

Best is to start with pawn structure: no permanent weakness (double pawns), two pawn chains same kind each side with only difference c2 vs d5 pawn, no passed pawn, center is not closed (with pawns).

Pure topic of square weaknesses: Black is better (only one weak square d6 for Black and two weak squares for White e3 e4). For diagonal weakness: the d3-h7 diagonale is weak for Black in current position.

Material is same but White is better developped (2 tempi) and White pieces are more active (enough to look at number of reachable squares).

Space advantage: obviously for White in center and kingside.

King safety: not so great each side. White is worse for king safety: no pawn on nearest squares.

My assessement is position is for White because of temporary advantages (developement). White has to keep piece on board (limit exchanges) in order to transform space advantage. White must castle quickly and after castle open lines on kingside. Black must try to exchange pieces, put king in safety and then use a classical pawn break f6 (to attack head of pawn chain since basis on h2 cannot be attacked easily).

Black is only one move for short castle and three for long castle. Short castle is here the normal one. For White castle is done in two moves (moving queen or light square bishop).

If White to move, White can play Qg4 one move to stop Black developping f8 bishop and short castle. It's White plan to long castle AND delay Black development. Of course Black can develop his queen,  knight on d7 or bishop on f8 before. 

If knight move: 1...Nb6 then 2.Qg4 Nc4 3.Bxc4 dxc4 4.ooo and now queen moves but situatiion has changed: always better development for White, and White can play Ne4 ... but maybe Black has counterplay. Thus we improve the line with 2.Bb5+ Bd7 3.Qe2 and now  knight cannot go to c4 without giving a pawn and 3....Bxb5 4.Qxb5+ Qd7 5.Bxb6. 

If queen moves 1...Qa5 then 2.Qg4 and if 2...Nb6 then 3.Bb5+ Bd7 4.Bxd7+ Kxd7 5.oo and Black king is unsafe in the center.

Best move is 1..Bc5 attacking the d4 bishop and oo to follow, or 1..Nb8 to play Nc6 next move. 

Bc5 prevents f5 because of Qh4+. White cannot reply Nb5 because of immediate oo.



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My view of position is despite White is a little better, immediate plan for Black is to exchange the good d4 bishop. The idea of f4 in the opening is not to improve the dark square bishop but to control e5 pawn. If Black manages an exchange of bishop in good conditions (for example if a rook goes to d4) thenBlack can play f6 or g5 to weaken pawn structure.

Here is a short survey of Boleslavsky variation (with Be3 and f4). Main ideas are control of a7-g1 diagonal and occupation of the blockade d4 square. Idea of blockade is common with advance variation and is part of Nimzowitsch strategy. 

A) 7...Qb6
first move to undertand because part of Boleslavsky main system. Game reference: Bronstein-Portisch,Amsterdam 1964 (Tiemann)
White attack at once the b2 pawn and add control to a7-g1 diag.
Now two  main moves: Na4 and Qd2 and one all purpose move: a3

A1) 8.Na4! (Boleslavsky plan: White attack the queen to improve control over d4) Qa5+ 9.c3  with 3 moves 9...cxd4!? (sacrifice of piece for pawns) ; 9...b6!? (a Khalifman suggestion, the idea is to exchange the bad bishop with Ba6);  9...c4 (Chandler-Vaganian,Leningrad 1987) 

A2) 8.Qd2 a pawn sacrifice for an attack. Ritov-Bistrov,Grodno 1988 (Short)

A3) 8.a3 (a move which deters Qxb2) cxd4! 9. Nxd4 Bc5 10.Na4 Qa5+ 11.c3 Bxbd4 12.Bxd4 Nxd4 14.Qxd4 15.Qb4 axb4= (White runs into a favorable ending)

B) 7...cxd4 8.Nxd4
Now White posts a knight,bishop or queen on d4 square but Black will attack this piece...and Qb6 or Bc5 are good moves because Na4 doesn' work anymore

B1) 8...Qb6 (as usual one main move to attack d4 and b2) 9.Qd2! (or 9.a3 transpose to A3 line ; now we see the poisoned pawn gambit in another position) Qxb2 (9..Nxd4 leads to ending which favours White with a grip on dark squares 10.Bd4 Bc5 11.ooo Bxd4 12.Qxd4 Qxd4 13.Rxd4) 10.Rb1 Qa3 and now White has some attacking plan. See for example: Bologan-Volkov,Rethymon 2003

B2) 8...Bc5 9.Qd2 
Modern line according to Nunn. Now White wants to long castle (in fact mandatory after 9...oo: 10.Be2 the pseudo sacrifice 10..Ndxe5! works)
Now Black has one principle move: 9...a6 and rare move Qe7, or the exchange on d4 leading to ending
9..a6!? and now White has 4 good systems: 10.Qf2!? ; 10.h4 ; 10.Nb3!? (Nijboer) and 10.Nce2!? 
Hudge thread on current forum is about Nb3

C) 7...a6
Preparing b5 and also Qb6/Qa5. Not good idea for White to prepare short castle because 8.Be2 b5= 9.oo?! Qb6
And now 8.Qd2! is best move (8a3 Qb6!?)
Then it follows 8...b5! (if cxd4-Nxd4 then game transposes to A or B lines above because Black cannot play b5)
and my best plan for White among the 12 moves (dxc5,Ne2,ooo,Be2,Bd3?!,a3!?,g3,h4!?;Qf2!?,f5,a4,Nd1) is 9.dxc5

D) 7... Rb8
Not so bad move, Black wants to play b5 without playing a6..but he need Qa5 and sometimes White plays a3 and Ra2 to forbid b4.
For example: 8.Qd2 Qa5 (8...c4 9.f5 b5? - 9...Be7 is Ivanchuk idea - ! 10.fxe6 fxe6 11.Ng5!? Hellers-Ivanchuk,Tilburg 1993 (Tiemann)) 
and now 9.a3 b5 10.Ra2!? Bologan-Korchnoi,Gibraltar 2005

After 1. e4 e6   2. d4 d5   3. Nc3 Nf6   4. e5 Nfd7   5. f4 c5   6. Nf3 
Nc6   7. Be3 



Many moves have been played. I think it is more important to understand the ideas in this position rather than memorising the moves.

I have never played 3.Nc3 before so I was hoping someone could give a brief explanation of 7...cxd4, 7...a6, 7...Qb6, 7...Be7, 7...Rb8 in this position.

I will probably end up having to buy the whole chessbase series on the 3.Nc3 french anyway but for now I would like to simply get briefly aquinted with it. I currently have the volume covering dxe4.