Asking a friend to hang out

This probably sounds so stupid but how do I ask a girl if she wants to hang ou?

I'm friends with a girl and have been for like a year, and I would like to hang out with her. She's sort of the first friend I've had who's a girl and I've never really spent time with any girl outside of school. I'm quite shy so i'm quite scared to ask her and i don't want her to say no or feel she has to say yes.

So firstly should i ask her even though i don't know if she'd like to hang out with me? Then what sort of thing should we do together? And then what should i say when i ask her? I'm probably just overthinking this but shes a good friend and i wouldn't want to ruin that.

Thankyou

we've both just turned 18 btw, so in yr13

You: "hey (insert name), we've been friends for a while now but haven't really done anything outside of school together before. If you are free this weekend, do you want to (insert activity - try going for a movie and meal). There is (insert movie name) that came out recently that I've been wanting to see, if you have anything else in mind that's fine too. What days are you free and what time?"
Her: "(says date and arranges if free)"
You: "Cool, see you then!"

you could mention a movie that’s on in the cinema and see if she wants to go with you. you could also invite other people along with her so it’s not as awkward. You could bring your dog on a hike/ walk and ask if she wants to join. Or go in a group of people and ask her if she wants to tag along. Don’t overthink it. Just don’t pressure her on her. Just ask it like “if you’re free one day next week would u like to go and do X?” and if she says no then take it as a no. She may want to do it on a different day

You make it sound so easy!!! Do you think it's better to ask her if she wants to do a specific activity or just ask her if she would like to do something with me sometime, then suggest an activity and a date if she says yes?