Seconding what others have said - you definitely don't need prior experience to boost your chances of getting into med. It's just unnecessary. Like Sine said, if you want to volunteer at a hospital, volunteer because you want to and not just because it'll look good on an application.
Also a note re: work experience - work experience programs in hospitals have limited positions and of course, during COVID, wouldn't be taking place. As far as I understand, it's not very common to be able to shadow doctors due to confidentiality reasons and the like. Often hospital work experience programs are based through the allied health team (which is still a really good experience - it's what made me choose to do physio).
I definitely recommend continuing to chat to the people you know who are doctors to get a good understanding of the good and bad sides of med. Don't stress about the lack of hospital experience - you get to experience hospital life when you do placement during your degree.