What's the difference between the following:

I got friends.

I have got friends.

I have eaten.

I ate already.

Any help appreciated.

Thanks a lot!
"I got friends" is colloquial. It means the same as "I have got friends" but the word "have" has been omitted. It is slang - do not use in formal English.

Compare with "I made friends", which refers to the act of acquiring friends, the onset of friendship.

"I have got friends" says that you have friends, and that the friendships are still continuing.

"I have eaten" is describing your mood in the present by way of explaining that you have eaten in the past. For example, in response to "Would you like some cake?", you might say "No thanks, I have eaten".

"I ate" (without "already") is purely a statement about the past.

"I ate already" is colloquial. I suspect it is intended to mean the same thing as "I have eaten", but the phrase is not in common currency among people I know, so I can't really say for sure.