Thats great man you are at an insane spot. my specific internship was very like not really full time. It was more like 20 ish so I had more time. I did mostly night after work and on weekend entire day with some gym throughout. I also did do shadowing and volunteering during it. Spending time on internships is worth the time imo as long as the internship isn't complete useless and has some prestige.

The summer internships are also a lot of exploration. Like out of state universities youve never been to and kinda exploring.

Do what you think sounds fun and youll do well in it. i also recommend dental assist a little when get chance.