Start by figuring out what you want abd need.
It looks like you want a strong art program.
You mentioned a recent ADHD diagnosis. Do you need a learning center that can support you with that? Would a more structured environment be better (i.e. assigned study halls)? Look at the schedule at Cambridge School of Weston. Some ADHD students find this format works well for them because they have so many fresh starts and fewer classes to focus on while others find the pace to be stressful. If you like this, there are others that have this or similar schedules.
You don’t have to share details here on your gap year or your decision to do online, but schools may want to understand that and if you are ready to independent and if they have the resources to support you.
Are you okay with a single sex schools?
For now, make sure you meet deadlines. There are plenty of schools out there with varying levels of rigor, different kinds of support, different academic calendars, and different vibes. You just need to find the ones that meet your needs.