Care and buses are generally not an option. You cannot exit Russia (sic!) on a car/bus/legs unless you have a specific travel purpose and "tourism" or "just because I want to" is not one of them. This was one of COVID-related restrictions and it's still in effect.

Trains are somewhat better, I guess: the Allegro train between Saint Petersburg and Helsinki is open for Russian/Finnish citizens only, but does not require special travel reason.