Here's where i'm stuck.  What to do after this move? Obviously move the knight, but where? Why do most lines teach to not do the immediate e5? And what should be my overall plan?

I mean playing as white, sorry

Nf5 looks good, as after bishop takes the d5 spot is a snuggle outpost for piece or queen or just come back to f3.  i don't like the retreat to b3 as it takes the bishop's retreat square.  Black backward d pawn can be a source of weakness as it can only be protected by pieces and not by friendly pawns.  In practice, black has been able to hold it in most lines, however.  White position looks rock solid and black will have to do something good to overcome his slight positional weakness.  Good luck.  and remember common sense is better than memorizing opening lines.

Nde2,nf3 and nf5 have all been played before