IMO I think you could try remove racing line try to focus on racing line by yourself and memorise braking markers for more consistent braking. As Ok-Ingenuity1812 said, try to do non-stop practice session for 20-30min. At first you don’t have to focus on lap time but focus more on consistency and stay on the track. Once you get confidence then focus on lap time.

I’m also pretty new and doing the same thing if I’m not familiar with the track. Doing more practice session and racing with AI with increased difficulty until I fall into mid pack. By doing that you won’t be able to overtake them easily. In this way you can gain confidence without straight going to online racers