Looking for opinions from current or former armed service members (especially British army)

Hello, I've wrote a story where the main character is a mixed-race British soldier (infantry) in the 1970s and 80s, initially just because I'm mixed-race myself and never see stories about people like me. Now that it's complete and I've edited it a few times I'm increasingly convinced the army stuff in it is cringe and inaccurate. I get obsessed with topics and read everything I can about them but of course that's not the same as actually having been in the army.

I was wondering if anyone reading this post might have relevant experience and mightn't mind me asking you a few things? It's mostly admin/procedural stuff, nothing secret. You'd be welcome to read part or all of it if you're interested. No worries if you're not, I'd just be very grateful for any information that might help improve it at all.

Definitely interested in swaps if you're looking a sensitivity/beta reader yourself. I could possibly help with: mental health stuff, race/ethnicity, LGBTQ+, culture (England mainly), trade union stuff. I've worked in the NHS for years but non-clinical. I'm ancient enough to have grown up without social media or mobile phones. Or if there's something else, please do ask.