Personally, I think you could do a healthy mix of both! For example, you can do an internship/ volunteering related to your field and then join a club for anything else you're interested in
Take advantage of your summers. As Ocean said, look into summer workshops/programs (like the Incandescent Summer Studio!). Attending these may also help inspire you to initiate projects on your own during the school year.
Start an art club at your school to teach younger kids
Workshops, summer programs, or independent projects (ex. writing a comics)
Community projects (ex. painting a neighborhood street), volunteering at local library/art center
Open commission on social media
Join The Incandescent art & web design team!
If possible, participate in your school's paper/magazine!
Should I only focus on extracurriculars that are related to what I think I might pursue in the future or should I just do whatever interests me?
Personally, I think you could do a healthy mix of both! For example, you can do an internship/ volunteering related to your field and then join a club for anything else you're interested in
Both! It's great to participate in activities you already enjoy, but pushing your limits and exploring new clubs is how you learn as a person.
Take advantage of your summers. As Ocean said, look into summer workshops/programs (like the Incandescent Summer Studio!). Attending these may also help inspire you to initiate projects on your own during the school year.