I was in the same spot for the first few years of my career and I regret staying there as long as I did. It really is easier to learn if you have senior engineers to give you feedback. My recommendation is to find a new job.

Failing that, I’m not sure what your relationship with your manager is like, but in most tech companies, part of your manager’s job is to help you grow. Maybe they could help you reach out to the few other tech people at the company to organize some kind of collaboration to help you all grow and improve.