1) I only wipe my feet’s with three fingers after watching my mother do it as a child and also saw it on YouTube, is it correct method or should one wash feet?

2) All my colleges are 30-55 years old. We don’t shake hands but say Salam by touching / giving knuckles, does that break the wudu? I work 2-9 and have to pray but many times I’ve been unsure of my wudu still on because of the knuckle greeting? Does thinking of a sin or swearing break the wudu? After wudu I take makeup on and leave the house, what’s the ruling of that?

1) You must only wipe the foot and three fingers width will suffice. You should not wash the foot.

2) Knuckle greeting or thinking of sinful things does not break wudhu. If the makeup has something najis in it then you cannot pray with that on