Any suggestions as to what I should do in a Gap year

I am planning on taking a gap year to retake 2 of my a levels. What things do you suggest I do during my gap year, particularly subject specific things to enhance me application for the next cycle. I will be applying again for mechanical or aerospace engineering.

Defo do lots of work exp, also u can look into degree apprenticeships and apply to them. They're litr a win win as you get paid a competitive salary, you get a degree for free and valuable work experience in an esteemed organisation, e.g Rolls Royce has an aerospace engineering apprenticeship. I had a gap year and went through lots of applications and after a vigourous 6 months, I now have a degree apprenticeship in tech. Also, I'll share this link, it might be useful when looking up apprenticeships. https://www.gradcracker.com/search/all-disciplines/degree-apprenticeships. They usually start looking for applicants in Sep - March, but I just checked and there are a few open right now, so apply even if u dont get the grades. They usually only require u to have 120 UCAS points as well. They can also be quite competitive but ultimately they're worth it. And if you dont get the grades, like me, its okay you can just retake, the world is not over.
The reason I'm rlly pressing this, is because not enough ppl know ab them. On my gap year i was quite confused and stuck until i found them. Apprenticeships are acc so underrated but so so valuable. I didnt know ab them until my older brother did one, and then now me, my cousin and my neighbour are all starting one this sep, God willing. So defo check it out. If you were doing med, nursing or any other qualification which requires Uni then yes, obv I wouldn't be writing all this. But there are so many engineering apprenticeships and it'd be a shame if I didn't tell you ab it.
I came across this the other day, it seems really valuable as you get paid and get a qualification so u can put this on ur cv and apply to fill up ur time. https://www.ratemyapprenticeship.co.uk/jobs/9930/city-year-uk/youth-mentor-gap-year-programme
Outside this, on my gap year, I also went travelling and i feel like I'm in a much better place so i highly recommend gap years, take time to focus on your hobbies, relax and learn more ab yourself. It can get kinda lonely sometimes and u might have FOMO as all ur friends might be going to Uni, but after so many years of being in the school system, I think it's really needed. Maybe u can get a part - time job to develop skills like communication or speaking skills to put on ur cv. E.g i did tutoring on my gap year and used that to show how i developed my communication skills. You can also develop yourself physically, like hit the gym - just take this year to rlly focus on yourself and become the best version of yourself. Wishing you the best!