RE: When someone doesn't value other people's time

First, learn more and be able to do the work myself.
In those three months, I carefully followed his every move and watched over his shoulder as he performed testing, chip replacement, and reprogramming, to see if I could go alone on tasks.

Second, I became better organized. I always had a bag ready with me, which contained three days' worth of clothing, so that I wouldn't let myself feel as donkey as I did that first time.

And thirdly, what I didn't do, because I soon found a better job (better paid at the start, in a big company, with the possibility of advancement and additional training), invite him to a meeting with the owner of the company and honestly tell him that it's not right to act like a jerk, because that way he will drive away anyone who starts working with him, and he definitely needs someone in the team, because the job is more demanding.
But if the owner of the company doesn't notice it, and allows him to behave like that, forcing people to leave the job, who am I to open his eyes.

There was one more thing I could have done, but I didn't want to, because the business with fuel and gas stations in my country is closely related to crime, the fourth would be to endure a year, learn everything he knows from him, collect contacts and start servicing as the owner of my own company.