PLEASE HELP ME WITH MY SUPER BOWL SITUATION *read please*

So there is this guy i like and he likes me and we are both 12 (no hate on age please)

We are like insanely good family friends and we will be going to a very small super bowl party at one of his friends houses together.

Both of our families, plus the friends family plus one of my best friends will be going.

So the backstory with this boy is that we have been best friends since pre school and we found out that we liked each other about ten months ago, but we are not allowed to date and i am too good for not telling my parents.

Every year at this party the dads are outside, the moms and me are downstairs, and the boys are upstairs

So i want to be able to spend time with him, but how do i go upstairs without it seeming weird? also do you think we can sit together (like not cuddle but be close) on a couch? just any tips on my situation would be great!

*i am posting this on multiple groups because i need some help and the super bowl is tomorrow*

UPDATE: it is like we are dating without the label of bf and gf