To be honest, this is the perfect time to start! You have two more years of highschool and starting your own initiative in the next two years is ideal. I would suggest you start your own initiative or passion project, especially because there’s more free-time than ever. Because your GPA seems high, I would say do some research or take a college class. As for projects, you could do anything from a virtual initiative, to planning a real-life event once things clear up, doing a fundraiser, starting an organization… there’s so many options and if I had this much time last year (I’m a senior) I would take advantage of it too!
Hope this helps and let me know if you have any questions.