How to go beyond A level Physics syllabus?

I am going to take the PAT this year (physics aptitude test) and while I'm very comfortable with a level material this test goes beyond the difficulty of the a level.
Does anyone know what I can read/watch to learn about more abstract physics concepts/experiments?
Or any advice in general would be great.

Isaac physics is amazing. They even have these small books for advanced content with questions.
You should check out the 2 A-level Physics books, especially the "How to solve Physics problems" one.
https://isaacphysics.org/pages/order_books?stage=all
Questions are free on the website anyway
This website is good for the Maths-y side
https://i-want-to-study-engineering.org/
And there is also the ENGAA practice papers
You could also try out the BPho practice papers
There is Round 1, Round 2 and the Physics Challenge. There are more challenges you can check out too
https://www.bpho.org.uk/Papers/R1/
There is also a really good book for problem solving my mentor showed me, which is called
"Professor Povey's Perplexing Problems" by Thomas Povey
You could buy the book or look on the internet if there is a pdf version...
ZPhysics, ScienceShorts on YT are good too.
Practicing questions are one of the most important it's great to see that you are studying for the PAT already, goodluck!!

Thank you this is really helpful!

If you go on YouTube you will find COMPOS webinars by Professor Vlad Chernov, Oxford University. It is aimed to teach students to go beyond A level Physics, and is a wonderful tool to learn how to do PAT questions.
You should have joined Compos if you were interested in doing PAT but ask around and see if someone has assignment papers for Y12. If you do them you will find PAT quite doable. The webinars are solutions of some of the questions from the assignment.
I think enrolment for Y13 are still open. If you get enrolled then you might get access to Y12 papers.