Yes, I feel everyone's pain knowing that there is a possibility that gyms might not reopen come fall, but here are some good ideas to stay active.
1. Go for a walk!
Whether it is on campus, home, or wherever you may be. Get some fresh air and clear your head from all of your troubles. This could be the perfect opportunity to meet new people, while staying socially distanced, find a new podcast, or listen to a new genre of music. Whatever it may be going on a walk may help you find it.
2. Go for a run.
Some towns are super hilly which may not be the best place to run, but like walking this is another great opportunity to clear your mind and focus on the one thing in front of you: Crushing your run. Being able to say you killed those hills on campus or your run in general will make you feel better as a person because you did something you didn't want to or think you could do.
Running is also a good stress reliever because you can set your own pace and try to reach a goal in the end instead of worrying about an assignment or paper due at the end of the week.
3. Full Body Workout
Bring a yoga mat to school or buy one for your house. Doing a full body workout inside of your dorm or outside on the track or grass will also help you mentally and physically. This will help because you are using your body as the weight instead of physical weights. This will help with mobility and muscle memory. By focusing on just using your body you are still pushing yourself but you are also teaching your body the right motion, so when it is time to hit the weights in the gym you'll know how to perform these movements exactly.
Basically what I am trying to say is find something active to do if gyms don't reopen. Start to prepare now because we don't know what will come fall. But being prepared by having workouts planned or a schedule for the week will help you in the long run because you'll be able to control one thing. That one thing is when, where, and how you workout, so that you can better yourself mentally and physically.