Biochemists, can work in a variety of situations. I can't brief all that here, so
here is something that might be helpful.
As for how hard it is to find a vacant place, that depends on specific situations of demand and requirement, by orgnaisations that employ biochemists.
Also: if you are not able to make up your mind, go through a quick review of job prospects in different disciplines,and then choose the one that offers the best job prospects related to the field you like (if you don't like genetics, for example, don't go in it simply that it has a good job value.).
I prefer molecular biology, and genetics. Right now, I'm thinking about an MBBS.