Hi Pinkykim
Highgate is on the Northern Line (Mill Hill/High Barnet branch), does Birmingham come into Euston or Kings X, if so it’s really easy to get the tube from there.
The station is an easy walk from there too, much easier than going by road as traffic can be a nightmare.
I’m from East/Central London, if you need any advice..
x
p.s. if you have a smartphone with apps, just pop the postcode into the maps app and it’s really easy!