About the kalam, the first premise is that "everything that begins to exist has a cause".

The first premise could also be "everything has a cause". They didn't use that one. They used the one where there's an extra condition tacked on it: it should begin.

Why is that extra condition in the premise?

It's a classical bait and switch. They make you think about cause and effect while you should also be thinking about the extra condition they sneaked in. The condition "begins to exist" makes no sense unless you get to the end and somehow "god" or whatever can be excluded.

Give me 5 examples of things that didn't begin but also caused things and justify why that condition is there in the first place.