People in STEM Jobs, where can we find them and what are good entry-level ones?

Its been about a year since I graduated from University with a degree in Marine Biology, and since then I only had one internship for the next summer, and while it was fine and was paid as well, I have been looking for a longer-term and permanent job within STEM, even going within broader subjects within the biology field. But as I looked, a lot of jobs I noticed either required a Master's or Phd, and/or skills and years of experience I don't have. While not all the biology jobs I applied for, were all like that, the ones that I have applied for, either some rejected me or I have still not heard back any sort of word from. I've been to multiple job boards and even through my university's career sources as well. So, I'm wanting to see if any STEM majors, and people here who work within STEM, have any sources, STEM-oriented job boards, other places, contact infos to any recruiters (and people who truly are looking for entry-level hires in the STEM field), etc. I dont want to go back to school yet, because I want to grow my skills and gain more to be able to have a stable and steady career. Thanks for listening, and I hope there is someone here who can help out.