Suggestions for Solo Travel in Europe?

Not sure if this is the forum I should ask in but in October, I’ll be flying to Europe from Dubai for around 5 days to take a solo vacation after a work trip. I’ll be by myself (29F). I’ve only ever been to Amsterdam and Paris (last year after this same work trip). My original plan was to fly into London and take trains around to explore and then possibly head home from Edinburgh or Dublin. Because of the fine print on an unused airline ticket, I have to fly out of a country that uses Euros and from somewhere of equal or more value. This puts me flying home of Amsterdam for the exact ticket value.

What I am currently thinking: fly from Dubai to London, spend 1.5 days there, take a LNER train to Edinburgh, spend 1.5 days there, and then fly to Amsterdam for my last day. I have a couple ideas on what I’d like to see. Please drop some suggestions below if you have any. Or if you think I could spend my time in other places in the UK better before I head to Amsterdam, please let me know!

I’m sorry if I sound inexperienced. I grew up without the ability to travel much outside of my home state and just recently have stepped into a job role that affords me opportunities to travel outside of the United States. I would love some travel tips and suggestions as well if you have any! Thank you so much!