How often do you miss prayers? How acceptable is it?

I’ve made some frum (non-hareidi) friends, and I’ve noticed they take shabbos and kashrus seriously but I don’t see them at minyan all of the time, and it seems like they on shabbos they sleep through shacharis and play board games through mincha. As someone who’s curious about being observant, I feel slightly embarrassed to ask whether this is them being lazy college kids, they’re praying in private, or it’s alright to just skip it when you’re not feeling it. What is normal?