Will A level biology be challenging for me given that I got an A at GCSE level? Thanks for the help!

It depends. A levels are a big step up from GCSEs and require a lot more work. Now this may sound weird but it's true- if you have a talent for biology or didn't have to work hard for your A (which is really good by the way) you will struggle more than if you had to work for it. If you work hard you shouldn't struggle too much but the thing to remember is that it's a big step up and only hard work can really get you the grades you want. Well done on your A and good luck for A levels!