Whether the gym in your area are closed or you just don't feel comfortable working out in them yet, you can get a great form of exercise right outside your door. Walking outside is free, you don't need equipment and you can stay as far away from people as you want.
Speed intervals are a great way to switch things up. Instead of walking at one pace the whole time, break up your walk into blocks and alternate back and forth between a regular pace and a brisk pace. This will get your heart rate up and improve your aerobic capacity.
Get those abs burning by squeezing your glutes and pulling your navel towards your spine. Make sure you are hitting the ground with a heel-to-toe foot strike as well.
In between walking intervals, change it up by doing a few squats or lunges. This target some of those bigger muscle groups in your legs.
Add upper body strength training while walking by including moves that target your back and arms.
Finally, take advantage of being outside and away from your computer and television. Breathe in through your nose and out through your mouth. This practice can help center your focus and move you through feelings of anxiety and stress.