I don't recommend doing medicine purely for the job stability. I'm doing biochemistry at uni atm and I have a lot of medicine friends- it's only first year and, even though biochem is also known for being a hard subject, they have quite a bit more work than me. If you know that you want to be a doctor, go for it. The goal of being a doctor and helping patients improve their health should be able to motivate you to get through it. But if you're just doing it because you like science and you'd at least have a secure job at the end of uni, then it's probably best to think a bit more about what parts of science you actually like more and what kind of career you'd like to do in the future.
Biochemistry focuses more on the cellular and molecular side of things (which I find more interesting than just anatomy, physiology and symptoms+diagnosing+treating disease). It's really broad- atm, I just finished the biochemistry, cell biology + neuroscience, pharmacology, and physiology + anatomy modules and next semester I'll be doing chemistry for the biosciences, molecular biology as well as continuing physiology + anatomy. In years 2+3 I'll be able to do modules such as genetics, cancer, epigenetics, neuroscience, metabolism, cell biology, developmental biology, immunity, proteins etc. etc. etc. I love how wide the variety of topics are and I love learning about the why and how of things, and things at the cellular/molecular level- in medicine you'll focus more on how to identify what's wrong with your patients because the aim is to be able to diagnose and treat (you also have to memorise so much it's crazy).
With a biochemistry degree, you can go into research and other laboratory based careers. You could also go into other areas like banking and finances due to the transferrable skills, teaching, and even apply to graduate medicine if you realise that you actually do want to be a doctor. With medicine- being a doctor is an incredibly tough career but it can also be really rewarding because of the impact that you could make to people's lives. If you like the idea of working with patients and being under pressure, then go for it and do medicine. Just don't do it for the wrong reasons. Try and get some work experience at a hospital (or a lab) if you can (although it might not be possible with the pandemic situation) but really think about what kind of career you would like/prefer.