Fitness help

I’m currently in a firefighter I program and I’m not up to par whatsoever fitness wise. I’m taking this class post EMT before I start a paramedic program. I had originally planned to work on my fitness before I started the program, but ended up going into it earlier than planned. With that being said I’m pretty pathetic when it comes to lifting items, swinging ax, ladder lifting, etc. I have a gym membership and I want to start training ASAP but I have no idea where to start. I’m looking for advice on a fitness plan/what to focus on in the gym to move in the right direction. Thank you for any advice!