A cousin of mine has been doing this the other way around. She is riding a bicycle home to Australia from London.
She made it across Europe and Russia, all the way to the Chinese border before Covid-19 hit and the Chinese wouldn't permit her to enter, so she has backed tracked to Tbilisi to wait it out before continuing.
You’ll probably enjoy “First Overland” [1], it’s a great travel story. There was an expedition in 2019 sort of recreating it[2] with one of the original vehicles and characters.