Getting a bike in the UK for a beginner

Hey all,

Kind of embarassing but I didn't learn to ride a bike until last week and i'm 25! I finally gave it a go and had so much fun that I picked it up quite quickly, even ending up going for a 5k ride without stopping!

I, however, don't have a bike of my own. What type of bike should I get to begin with? Where should I get it from (UK, Hampshire)? I'm probably not even asking the right questions with how little I know as of yet.

I'd love to properly get into it and go for long rides one day, exploring the country around me on a bike.

Thank you for any help you can give!