I'll be honest - Law is an EXTREMELY competitive degree at university. I am also not applying for Law, so I can't be of too much help. But if it's what you want to do, don't give up hope. The fact that you have any extracurriculars is great, so make sure those go into your personal statement - and expand on what skills you showed/gained during these.
Your predicted grades will be sent with your application, and they look pretty good to me. However as I said, law is very competitive, so I don't know how much better everyone else is. Definitely request to get that B moved up to an A, and then I think you stand a better chance.
GCSEs, while looked at, shouldn't matter too much - it depends on the specific university in some cases, so look at the admissions requirements pages for places you're thinking of applying to, and see which ones fit your grades if they mention GCSEs. TBH, since you've at least high passed your English exams, I think you'll be fine - most unis with essay courses probably just want a 5 in English.
Good luck, I'm sure with your dedication the path forwards will be attainable. I hope someone with more law experience comes along to help you out more, too!
P.S: while Russell Groups seem to ask for high grades, I managed a contextual offer from Uni of Manchester (I didn't even know I was eligible lol) with "WP Plus" - meaning my school and postcode both counted towards it. I only need a BBC to get in for Latin & French, so with that in mind, I think you defo have a shot!