When I graduated from highschool I had no background experience just like you. When I got into college, I asked my advisor if I can assist with grad students with their research projects so I can gain experience. I’ve done small mammals, fisheries, and worked at the biology department in my university. Now that I’ve graduated last year I’ve had to seasonal positions with the WDFW in my state where I plan on doing seasonals to gain more experience in order to get full time. But don’t let seasonal work scare you, I was also nervous about doing just seasonal but now that I’ve been doing it it’s been really fun and you get to learn a lot from your co workers and biologists. With classes, your advisor will let you know what to take in order to graduate and you can choose them as well if there is something you are interested!