General saving advice (21 year old)

Hi! I’m lucky enough to have been saving for quite a while as I worked through uni and have been savvy with money. I opened a natwest regular saver with 5% interest years ago and about to hit the £5k high interest limit!

I have another savings account within natwest, with 1% interest that I’ve stored money in for years, but I’ve always needed access to this money in case of emergency at university as I wasn’t earning a lot. However, I’ve started working now and am earning just over 2k a month, I live relatively cheaply (live outside of london and commute, so rent, utilities & tube costs are my biggest expense at around £1100 a month combined) I’ve found my savings are growing faster then I anticipated and I’m not sure what to do with my money now?

I eventually want to buy a house, but the market is so volatile right now and I’m not even sure where I would buy. I’ve moved to a town just so I can commute and it’s nice but i’ve not lived here enough to imagine settling down here. Anyway, a LISA feels to permanent as who knows what the future holds and I don’t want to tie my money in to buying a house when I’m only 21. Stocks and shares ISA feels best but I would hope I can buy a house in the next 10-15 years and I’m not sure the returns would be great that short term.

any advice would be appreciated, I want to make sure I’m doing as much as I can to maximize my returns and set myself up for the future!