提交给 vs 提交 difference What's the difference between :
提交给 and 提交?

What does 给 indicate when it follows words like 提交, 借, etc.?

And should I use 把 whenever I use words like "return", "submit", "hand over", etc.?
提交 is merely an action. 提交给 requires a word to refer to the person who review/read the thing you submitted.
给 means "to" in English. When it appears right after 提交, 借 etc., it needs you to provide a word right after 给 to refer to the person that you submit [sth.] to or lend [sth.] to
把 is used in some expression like "send the book to you" which could be translated to "把 书交给你". Usually the word “把” does not have an explicit correspondence in English. For those words you've give, you could use “把” when you mean "return/submit something to someone". In other words, if you want to state the receiver, then you should use 给.