making patches and fixed .exe files

[Awolaviator]

hi,
just another newbie totally confused on how to make patches.. or fixed .exe files.. i would like to learn just for the sake of learning. i have a few games i would like to make fixed .exe files for and patches for but have no clue where to start.. would some on please point me in the direction i need to go to start..

thanx

ps.. sorry if this question has been asked before .. couldn't find it in the searches.. kinda computer stupid..