First wedding! Tips/advice??

Okay I’m going to my first wedding this July. It’s my boyfriend’s friend. I’ve never been to a wedding before!

What do I need to know?

I heard you apparently aren’t allowed to wear white? Is this true? Can I wear a black dress? What other dress code rules are there?

Is there anything else I should know about that you just don’t wear/ don’t do? Do I bring a gift? Are there rules for that?

Also I am going as my bfs plus one BUT he is in the wedding party so what do I do while he’s at the front? Or whatever it is that groomsmen do. Is there like assigned seating? What do you do as a groomsman’s plus one?????

Am I expected to dance??? What type of dance do people do at weddings? What does the schedule of a wedding look like?

Ahh so many questions!!!