Ah, just seen your original post.
You’ve got a bit of a decision to make to be honest.
If you want to enjoy all of the atmosphere in and around the ground up until and after kick off you’re probably going to have to stay nearby if you want to watch the match. Anywhere else in London worth getting to is going to take you up to an hour to get to. Would be a bit of a pain in the arse to try do both you’ll be wasting time on trying to navigate busy trains.
You can try to find a Wembley pub - although it is difficult they actively try and discourage people doing what you’re doing to keep numbers down. Personally if I was desperate to savour the atmosphere as much as possible, and I had a place nearby, I’d plan to be out for as long as possible then go back to my place with some beers and watch it there (if you can stream it) then get back out after. You can check out pubs in Wembley through the day and see if there’s any that might be an option.
If you do want to leave Wembley, then you should find one of the places that notoriously serve the train lines that go there, like Baker Street, Euston or Liverpool Street and narrow it down that way.