Struggling to find protein that isn't chicken

This is the first time I've seriously meal prepped (I'm a bit of a foodie, so it's been a challenge for me to not get bored of the same food). I've been doing it for a month now and I'm struggling to not get bored of chicken breast. I've also had fish a few times a week, but I've read in some places that you shouldn't have fish more than a couple of times a week.<br>It's also not ideal that I have a small fridge, so that prevents me from buying other protein sources like beef, lamb, or pork (because they have higher fat content and go bad faster). <br>If you have any suggestions on what else is relatively long lasting and doesn't go bad quickly, I'd really appreciate it. TIA for your help!