Start with Python. https://www.learnpython.org/
Also learn databases - start with sqlite, because it doesn't require a server. UnQLite is also a good db to start with - it's up to you to learn the difference between SQL and NoSQL. Learn html and javascript. There is even a programming language based on javascript called nodejs that can also be useful.
I believe these are good places to start:
https://www.tutorialspoint.com/index.htm
https://www.codecademy.com/