"Even if" refers to something that may be conditional - it may or may not happen. Also, "even if" must be followed by a complete phrase, including a verb. "Even" implies something is certain. It can also be followed by a complete phrase, but can also be followed by just a noun and modifier. "Even if you started now, you could not get there in time." [This is conditional, because you haven't started yet.] "Even Steve agrees." [This is certain that Steve agrees. We did not expect it, though, so "even" is used.] "You couldn't by it, even for two hundred dollars." [Again it is certain. There is no complete phrase here, either.] "Despite" and "in spite of" are used to describe some event or obstacle that would tend to stop A, but A happens anyway. "We enjoyed ourselves in spite of the rain." [The rain should have stopped our enjoyment, but it didn't] "He ran despite having a sore leg." [The sore leg might have stopped him from running, but he overcame the pain and ran anyway.]

"Even" is just for emphasis, it's usually said before something especially impressive or especially bad. For example: He plays the flute, guitar, and even the violin! He is so bad at school he even failed recess! "Even if" is a little tricky. The sentence must have two parts, one part that is something you plan to do and another part that is a reason not to do that thing. "Even if" goes in front of the reason not to do something and means that you plan to do it anyway. You can say: I will study theater, even if my parents don't approve" that means the same thing as "My parents don't approve, but I will study theater anyway." "Even if you think I'm fat, I will eat the cake." means the same thing as, "You think I'm fat, but I will eat the cake anyway." "Although" is the same as "even if", but the reason not to do something when using "although" is more certain. For example: "Although my parents disapprove, I will study theater" means that you know that your parents disapprove. "Even if my parents disapprove, I will study theater." means that you don't know if your parents will disapprove, but it doesn't matter either way. "despite" and "in spite of" mean the same thing as although, but we don't really use "in spite of" except in the phrase "In spite of everything". "Despite not having any money, she still bought shoes" "We bought her dress, shoes, and makeup. In spite of everything, she decided not to go to the dance." I hope this helps! It's kind of complicated.