beyond A level
Some advice and courses intended for those who are taking (or have taken) Maths/Further Maths A Level and are thinking of next steps. There's plenty of useful self-study material available, and this page has links to some ideas for further reading, online courses, etc.
If you're interested in programming and data science (and this really is a big thing at the moment), check out this Coding for Data Analysis OU course (24 hours of study) or this longer Python for Data Science MOOC (80 hours).
I would recommend learning and using Google Colaboratory for coding in Python.
Coding skills for science students
The use of coding is becoming more and more important in sciences and university students are unlikely to get away without being capable of using a variety of programming packages.
The MEI Further Maths A Level paper Further Pure with Technology is a great introduction to programming in a mathematical setting, and introduces spreadsheets, some Python and the use of Computer Algebra Systems. There is a video based course available here and past papers (from an older version of the paper) here.