Advice on how to structure contests

I'm a pretty new dm, so I decided to ask for advice on how to make contests more than just rolling a dice. right now my players are about to enter a randomized contest with three different events, with those three being absolutely anything, as long as it's decently fair. Like no animal parkour or something if a druid is participating. I have two questions, number one, what are some good events, if it can be absolutely anything? And number two, is there a way to make the contest something other than rolling skills?