For my GCSEs I got a mixture of A* and As. At Level, I took Biology, Chemistry and Physics and I the got 3 A*s (my offer was 3 As).
When applying to Medical School, most universities will make you an offer of 3 As. Also some universities look at GCSE results and some don’t so it’s a good idea to check out the entry requirements of different universities and apply to the ones that you fit the criteria for. Some universities run Widening Access schemes which means they would reduce your entry requirements if you got an offer for them (there’s certain criteria you have to meet to be eligible for these schemes).