I'll (do something)

Use "will" to offer to do something, or when you've just decided to do something like in these situations:

OK. Well, I'll take it.

I'll keep an eye out for it.

("I'll" is short for "I will", of course.)

When you've been planning to do something for a while, don't use "will". Say "I'm ___" or "I'm going to ___".

We're going to keep it to just close friends and family.

I'll see (someone's bet)

When you're playing a card game like poker that involves betting, each player takes turns making bets. When one person bets a certain amount, everyone else must either "see" the bet, which means to bet the same amount, or "fold", which means to give up and lose that round.

So when telling a story about a poker game that you played, you might say:

I wasn't really sure what to do, but I saw his bet. It turned out that all he had was a pair of aces.

raise (someone) (an amount)

In poker and other gambling games, "raising" someone means betting even more than they did.

For example, imagine that Player A bets two dollars. Player B "raises" Player A one dollar, so the bet is now three dollars in total:

I'll see your two and raise you one.

Then the other players, including Player A, need to match that bet or "fold", which means to give up.