ani okhel lifnei ha yladim
So is this just for time? Or does it also mean 'i eat in front of the kids '?
Both, but the latter can also be translated as "אני אוכל בפני הילדים".
Another question said מולו means "in front of him". This doesnt look anything like "לפני" . Whats up with that?
Not clear to me what you're asking.
Some other questions put "ש" after "לפני" but why doesn't this question?
If the thing after לפני is a complete sentence, you need ש. If it's just a "noun phrase", no ש. So, אני אוכל לפני הילדים but אני אוכל לפני שהילדים אוכלים (I eat before the children eat).