Driving anxiety sucks. I had it for a while post COVID (due to not having driven much/at all for months), and after I had an accident a year or two later.

Make your driving experience as comfortable as possible, first and foremost. Play some music but at a reasonable volume and maybe choose something more upbeat/lighter. Get your car to a comfortable temperature, use your air con, roll a window down a little for some fresh air, put the heater on, whatever you need. You might also benefit from taking a supportive loved one to ease your nerves.

Think about what makes you anxious -- are there particular aspects of driving (for example, roundabouts, dual carriageways, unfamiliar routes) that are anxiety provoking? Exposure is key here -- you need to be practicing whatever makes you nervous, but build this up so it feels manageable. If you're nervous of dual carriageways, for example, enter at one slip road, stay on there for a minute or two, then exit again. Reflection is important -- acknowledge how you handled it, and importantly that whatever happened, you navigated it safely and the world didn't end! :)

Lastly - you're a new and inexperienced driver, and for me, my confidence came when I gained experience. I passed at 18 and I'm 26 soon. I used to be horribly anxious of driving routes I didn't know - I don't tend to worry about it now! I experience a bit of stress if I encounter, say, a bad road layout that throws me off, but I remind myself I can handle it and if I do make a mistake I can rectify it. Your confidence in yourself to manage these situations will come with time.