Your question is not crystal clear. If I understand you correctly: the phrase 'get together' means 'to meet some other person(s) somewhere'.
Often, perhaps even usually, the meeting will be for something fun or entertaining, but serious work can also be implied.
"Let's get together!" Context: it was great to see you today after all these years and I'm happy to hear you're back in town. Let's plan to meet [e.g. for drinks or a coffee] at some time in the near future.
"Are they going to get together after the meeting?"
When the meeting is over, are they going to meet afterwards [e.g. for drinks]?
But it could also mean:
When the (public) meeting is over, are they going to meet in private afterwards to discuss their differences and try to settle the dispute amicably?