It's all ok, this is a scary transition period. As a fellow 2022 biomedical science graduate who is job searching, hopefully you can feel less alone.
I think the first thing to do is find an immediate job to give yourself something to keep you busy, give you more transferrable skills and a more recent thing to put on your CV. Think supermarkets, restaurants, pubs, care homes.
Next, do you want to work in lab, or in an office or teaching? This is just to help give you some search criteria for jobs. Remember your first science job doesn't have to be your career job, it's just getting your foot in the door. Do you even want to stay in the science field, or does doing a graduate scheme to train for example in human resources appeal?
Use your careers service! Use their search engine, see if they have any job postings as they can be specific to your uni and so there is generally less competition. Talks to a careers adviser for more specific advice and run your CV and cover letter that you've personalised for each job last them.
Any job or volunteering can be used as an example of transferrable skills, and the more recent the better. This is why getting onto some job or volunteering right now is crucial.
I'd say just don't do a master's because you're unsure of what to do next, as you'll most likely just be in the same position a year or two from now.
Prospects website has a page on what you can go into with our degree, so you might want to give that a read.
You can't change what you did or didn't do in the past, but you can get the ball rolling right now to put yourself in the best position possible.
You've got this!