What camera would you suggest?

I quite like Nikon and canon camera's I'm 15 so i don't want anything really expensive, anything up to about £350

I like the Nikon D500 but its too expensive

Not much left to suggest is there. You can get into a Canon t3 for around your budget.

A Fujifilm S4250 would cost a lot less than that, and allow you to learn.

Nikon D3100 Digital SLR Camera with 18-55mm VR Lens
£264.99, http://www.jessops.com/online.store/categories/products/nikon/d3100-digital-slr-camera-with-18-55mm-vr-lens-78032/show.html

Best answer get a two thirds camera like Nikon J1. Or Sony nex series

Be the way to go