Hi, can anyone recommend a good race for a newbie who's based just south of London (Reading)?

I've seen Box Hill and wanted to give that a go but it's well and truly sold out.
I believe there are a few on the Isle of Wight as well but wasn't sure what a good option for someone with limited navigation ability and almost no time on 'serious' hills?

I want to get onto some of the tougher races in time but the lack of navigation experience & not much time on the fells make it hard to know where to start.

Appreciate there are a load of similar questions on here but being the wrong side of London I'm going to end up with a serious drive to get anywhere and wanted some advice where to start.

Thanks everyone.