The foundation for an IT specialist?

Question

IT education

Greetings. I am 19 years old and serve in the army. I have enough free time and a smartphone. After the army, I plan to study swift. Until then, I don't want to waste time. Of course, I can’t study swift now, there is nowhere to practice, but the theory is possible. Advise me materials, literature (programming, algorithms, mathematics) to lay a good foundation for a future IT specialist.
Thank you.

Answer 1

Impossible!
Without practice with bare theory, you won't learn anything about programming.
Learn what you can install on your smartphone (IDE) and practice coding directly on your smartphone.