How to get into genetic engineering if I have no formal background?

If you mean something on the biological side of things like CRISPR, the answer is pretty simple: you don’t. Biology weighs formal education, especially when hiring, very very heavily, and the odds of getting into the field without any are pretty much nil.

If, however, you want to work on the engineering side of companies that works with genetics like that, you’re much more in luck. I work as a swe at a genetic diagnostic company, and while my background is in biology, the vast majority of devs do not share that background - it’s too difficult a niche to fill. Instead, mostly what we look for in hiring is an interest in the field. We have plenty of PhDs that worry about the nuances of biological complexity, and enough devs that understand enough to bridge the gap between them and people that have zero biological background. We trust that we hire devs that have the ability to - at the very least - get up to speed enough to be effective, so that’s what we look for.

Start with an entry-level job in an MCB lab (standard bench work: pipetting, plating, PCR/PAGE, wet chemistry, etc.), and build upon that experience to get opportunities to do more sophisticated techniques, eventually leading to genetic engineering work.

Essentially, the path I'm recommending is a career in microbiology. It's admittedly the long road, and not a well-paying one at that, but it's one way to do it!

https://www.youtube.com/watch?v=odE8dNcklks

I wonder if there is something for hobbyists to get a taste of lab work and experiments.