Got A Job, Been “working” With No Uniform, No Job Offer, And Background Check Isn’t Even Completed. Is This Illegal?

Hello everyone, I live in California and I just relocated to a different city. I’ve been struggling to find a job for awhile and I interviewed at this place a couple days ago. The interviewer hired me on the spot and asked me to come in Friday (2/14/2025) to submit my forms. She sends me a text on Thursday (2/13/2025)night asking if I wanted to start training on that same day. I happily obliged, since I was excited to start working and make money. When I got in on that Friday, I was confused as she didn’t ask for my forms right away. She just told me to start my computer training and she would get to it. Later in the day (like 5 hours in) she finally takes my ID and my birth certificate to scan. But I still haven’t received an offical job offer. Later in the day, she asks me to reapply to the job which she couldn’t even find the link to until about another hour later. She finally finds that link, I complete it but I noticed it’s to perform a background check. I ask when this background check will be finished and she said about 4 days. This was when it got weird, she started putting me to work. Told me to shadow her and watch what she was doing and to help out. Mind you, I don’t know my pay still, I don’t have a uniform, I don’t even have a clock in number or a set schedule. I “trained” yesterday for 8 hours, and then today for another 8. I sent her a text asking when I’ll be paid for these hours and haven’t gotten a response. Finally, I have never gotten my official job offer, and I’ve never signed any tax forms, or any papers on the companies policies and the job description. I thought I might add, I saw another gentleman at work who also wasn’t in any uniform. I asked him when he started and he told me he started a few days ago? Any legal advice will be helpful or advice in general. Thank you.