Anyone Had Any Experience Co-teaching Alongside A Teacher In HS?

So I’m a sophomore in HS, and long story short, my freshman Biology (non-Honors/AP, regular College Prep) class teacher was amazing, Made class interesting by relating topics to our daily lives (sometimes with unnerving info I’d prefer to forget lol), and I did really well in his class. He Inspired me to want to pursue a Biology major in college. On the last day of freshman year, I asked him about Co-teaching, to which he replied “Yeah, you’d be a great candidate. Keep in touch and see me at the end of sophomore year. Have a nice summer.”

This is something that i really want to do, but I’d have to not take a foreign language (Spanish 3 & AP Spanish) during Junior and Senior year in order to fit Co-teaching into my schedule. Your thoughts?

Has anyone else ever co-taught alongside a teacher in whose class they did well in? I assume you helped teach lessons, grade assignments and stuff? What else did you do? What did you enjoy and dislike about it?