Just don't deadlift nor barbell squat. It's that simple
Anything else that involves your lower back you do it slowly. You also increase the weight slowly. Use a belt if needed.
Do that, warm up and do stretches on non-training days and it's hard to get injured. DO NOT listen to the stupid cultists in this site, do whatever feels best for you and try things out first to see if they're a match for your own body.
When I started lifting I did squats with low weight and I still felt discomfort in my lower back despite checking my form with multiple trainers. I stopped doing them and now I just do machine isolations, and guess what... They still work to develop your legs.
>But the erectors
Hyperextensions