General advice about various things surrounding gap year after missed offer

Not sure if this should be here or somewhere else as it's a bit of a combination of different topics so yeah.

I received my A Level grades today (A*AA) and unfortunately missed both my firm and insurance offers by a few UMS. I'm getting two papers remarked but realistically I don't think they will change. Even if they do, I think my university will be full and the best they could do would be to give me a deferred offer anyway. I don't fancy anything in clearing and have rung up several other unis just to check they can't offer me a place, before anyone suggests that.

So I'm trying to think ahead and turn a failure into an opportunity to benefit from a gap year, get some experience behind me and hopefully travel a little bit too. I'm in the middle of an internship at the moment and they've already hinted that they would let me continue there for another 3/6/12 months if that's what I would like (they've done this with interns in the past too). I'd like to stay there for maybe 3/6 months but if I could, I'd also like to try somewhere else. However I know that trying to find a paid internship at this time of year will be more or less impossible, especially that's useful to banking as that's what I'd eventually like to do. I'd love to go live in London for a few months and intern there, even if it's not quite directly related to banking, but I don't think that sounds feasible.

The only thing is that I really don't want to live at home anymore. I can't cope with living with my mum for any longer, she doesn't care about me and was trying to push me to go to unis like Sheffield Hallam through clearing just to get me out the house sooner. Not trying to insult Sheffield Hallam but I'm trying to remember that although I got rejected, I got some decent grades and I think I could do better. I found texts on her phone of her like "oh my daughter missed her offer I'm so upset as I'll have to put up with her for another year" etc. I confronted her and she said she wants nothing to do with me. So I'd like to move out but I have nowhere to go and next to no money. All of my close friends got into uni so I can't go and stay with them, nor do I have any family to stay with.

I'm going to resit 2/3 papers to hopefully bump my grades up to A*A*A* as that's what I was predicted at the start of this year and I know I can achieve that. I'd like to travel as well, but I don't have any money really (my parents don't give me an allowance or anything and just give me money when I need it for something, and I don't think that'll happen anymore) and I'm a bit scared to go on my own as my friends will all be at uni.

So yeah, any advice whatsoever is appreciated, whether it be about how to plan a spontaneous gap year, where to live, travelling... Sorry for the long read!

TL;DR - missed uni offer, taking a gap year unless remarks come back successful (unlikely). Can continue with current internship for a few months but would like to look at other (preferably banking/finance/economics related) internships if possible. Want to move out as really don't get along with my mum but have nowhere to go and not much money either. Finally would like to travel but not sure how/when/where/who with