Meaning of “so” - Learner’s Dictionary

so

conjunction uk us /səʊ/
REASON

A2 used to say that something is the reason why something else happens:

I was tired so I went to bed.
Greg had some money so he bought a bike.
so (that)

B1 in order to make something happen or be possible:

He put his glasses on so that he could see the television better.
CONNECT

A2 used at the beginning of a sentence to connect it with something that was said or happened previously:

So we're not going away this weekend after all?

(Definition of “so conjunction” from the Cambridge Learner’s Dictionary © Cambridge University Press)