But I'm not very smart, for example, can you explain why Bc5 is such a bad move please?
It appears to be defended by the N at c3.
I'm not that smart either, and I"m not sure I can, but I'll try. I hope a more respectable French expert can (gently) correct me where I go wrong.
The issue is that the only real purpose of the move is to either exchange the bishop off, or use it for a mere tempo or two to restrain the knight.
Exchanging it off is bad because it is white's good bishop. It's doubly bad to exchange it off for black's white bishop which is easy enough to have happen in some lines, because black's light square bishop is black's bad bishop.
In the advanced variation, white has created a locked center with pawns on dark squares pointing towards the king side. The light square bishop for white is an impressive and useful weapon for pressuring the king side with such a pawn formation. But playing it to b5 at least puts it out of play and at worst trades off one of white's best minor pieces for black's worst.
It's just a positionally horrible move.
1. e4 e6 2. d4 d5 3. e5 c5 4. Nf3 Nc6 5. c3 Qb6 6. Bb5
*
is the moves I entered. Not sure why it says "white to move" It should be black's move in that position, I'll see if I can figure out how to change that :)
Also looks like an exchange of pawns happened, maybe
4. c3 cxd5
5. cxD5 Nc6
6. Nc3 Qb6
7. Bc5...
But I'm not very smart, for example, can you explain why Bc5 is such a bad move please?
Got to be at least in part because it's impossible.
Yeah it is.
Sorry, meant last move to be 7. Bb5