Are beach umbrellas allowed? And are tents allowed on the beach? - the kind with one side completely open.

It was my first time that I went and I find myself, there is a lot of shade, benches to put the food, there are meat grills, games for children, the only problem is that you have to go very early because if the parking lot gets full they won't let you in, I was there at 7 and 5 in the morning and there were already enough people

Yes

Yep and yep!