As an obsessive pure mathematician who is obsessed with twisted forms of coding minimalism to stave off boredom and so on, and who did his PhD in arithmetic.
1. You learn to count from 1 to 100 so well it is effortless.
2. You do so in a way that is fun (e.g. snakes and ladders).
3. You learn to code.
4. When your coding problems require mathematics, you look it up in a book.
Crucially, if you do it this way, you will have motivation to learn the hard maths. Really, motivation does seriously make a difference here.