I suppose youre question is about:
1.e4,e5 2.Nf3,Nc6 3.Nc3,Nf6 4.Bb5,Nd4
5.Bc4,Bc5 and now
6.Nxe5,Qe7
White can indeed play
7.Nxf7, Rf8 8.0-0, b5!? and black equalizes without difficulty
Black can even 'risk' 7.Nxf7,0-0 as
a) 7.Ng5+,Kh8 8.0-0,d5! (9.exd5?,Bg4! -+)
b) 7.Nd6+,Kh8 8.Nxc8,Rac8 9.0-0 (9.d3,b5!?) ,Nxe4
Here the move ...d5 comes into play. As long as white hasnt castled his kingside is extremely
vunerable (especially the point f2).
It's not as if 7.Nxf7 is bad, but that 7.Nd3 is better.
By the way
7.Bxf7, Kf8 8.f4,d6 isnt something I would recommend