The weekend is here, a time to relax from work and strenuous activities during the week, but you might want to spend the weekend resting, resting alone can be boring.
So to invite someone over for the weekend, here is a simple way to invite a friend with courtesy:
1) What are you up to?
What are you up to is a casual expression for what are you doing, or what are your plans.
In another example sentence, what are you up today? Come… with me.
The next expression is come bah bah bah with me. So here this space come do something with me is a noun phrase. Come to a movie with me, come fishing with me, come to a concert with me.
This speaker is inviting you to join him/her. It’s a stronger invitation, they use the command form come bla bla bla with me, it’s a command form phrase.