does the upload speed depend on the upload speed the isp gives us or does the lan cards in my PC play a role in it
The upload speed you get will be the lower of the capability of the LAN card and the speed your ISP provides. The latter will almost always be lower.
Almost always the ISP unless you are truly using an dinosaur.
Sometimes a Disk Clean Up and a run of MalewareBytes will help.You have to be a little bit crazy to keep you from going insane.