How do you make it so players earn points

I do not know how to do this?

what do you want them to do in order to earn points?

Whatever they do could increase a counter, which could then update a property that the score is based off of.

how is the points calculated, like how will the players get points?

Your point system could be a certain item. If you don’t want people to give points though, you would have to disable dropping items.
Also welcome to the forums @mroets !