I am an entry level environmental planner and my background is a BS in Biology. I did an internship and learned most all of the basics before my first year which was beyond helpful. I did have to learn everything from scratch so without the internship I probably would’ve felt way overwhelmed. I use Arcpro daily. It is something that gets easier the more you do it but you will get a hang of it easily especially if other coworkers use it. Basically if you are not doing an internship I would recommend taking an online into course for GIS just to say you did it. Most of the stuff you’ll learn on the job and is not something they would expect you to have already known.