3rd year medical student who can teach Maths and Biology at GCSE and A-Level standard

I know Adam since I'm his brother. Being older than me, I saw him as a role model, always achieving excellent grades and working to achieve his goal of studying medicine at university. Eventually I required help in A-level maths, and I immediately thought of Adam so I'd ask him for help on concepts and questions and would always understand it at the end. He would be able to explain the step by step solutions calmly and with a sense of understanding. I remember one probability questions we came upon and even confusing him but he did not give up and kept trying different methods when I had already given up and of course he solved the question, achieved full marks on it.