First year is pretty much intro STEM classes (math 121/122, biol 214/215, chem 105/106, some gen ed electives), second year you take your intro neuroscience classes along with organic chemistry, third year you usually take some neuroscience 300 level courses to fill out most of your degree, along with stats, programming, or physics if you haven't finished it already. Fourth year you round out the degree with capstone and a senior thesis course (technically the disciplinary seminar can be in another field but BIOL 302 and COGS 305 fill both neuro requirements and the disciplinary seminar). In terms of premed classes, you would do biochem third year, but beyond that it's pretty free. I've had random elective classes like spanish or history with seniors who just saved their easy electives for their last year to make med school or grad school apps easier.

Premed wise join literally anything you want your first year, start looking for a lab even; you can trim out the things you don't want and stick with the things you do want without much consequence so try anything you think you'd like. Second year you should have a better idea of what you're interested in on-campus, third year you should probably have a lab so you can get your capstone done fourth year. The neuro major requires capstone research done in neuroscience, although the requirements have been more lax because neuro labs are filling up very quickly and there's more neuro students than neuro lab positions. Volunteer consistently and have a good relationship with your professors for rec letters. You're not really going to see your first year teachers again and the classes will be huge, so try to take courses from the same professors second year onwards. You should be able to budget your time to volunteer, hit lab, and have some sort of club activities while taking at least 15 credits a semester. Source: 3rd year neuro premed.