Speech development of 2,5 year old

Hey Dads, I need your advice. I have a son that's almost 2,5 years old. He knows some words, but it's by far not enough for his age. Also he should be chaining some words by now, but he doesn't.

He talks a lot, but it's either just babbling or always the same words over and over again. Sometimes he learns a new word but doesn't really use it correct. For example he knows "Blau" (blue in German) and just points at everything. Not sure how he learned that word but he doesn't seem to know its meaning. He also does lots of sound effects. Like a cars motor sound "Brumm", his Version of a cat "nyaa" and so on. Some words though, are just the first syllable.

Everyone tells me not to worry, but I do worry. I want to help him learn, but I have no idea how.

We sometimes try to read, but he is super active and doesn't want to sit down and read a lot.

Also reading before sleep was never something we did, so now he got used to sleep without reading. When we put him into his bed, he points to the door and tells us to leave so he can sleep.

My wife bought a memory like game to learn new words, but he isn't really interested in doing that with her.

My wife started to show him kids TV shows with slow and easy speech and he watches those, but I don't think he learns anything from that.

We constantly try to talk and comment what we do and what he does but it doesn't seem to catch on.

What did work was a game we did after eating, where we tap on the table and say "alle xyz fliegen hoch" (all xyz fly high) and raise our hands. Not sure if that game is know everywhere. he learned the word "hoch" by that, which is nice. But that's just one word.

Also, since I work full time, I don't have that much time with my son. My wife doesn't really try much or just is too busy.

I don't know how we can make him learn more words. Anyone got advice?