C++ author, trainer
Nice to see that you like doing projects. This is the phase in which you actually build a product.
Familiar with the second sentence when I was young. But I think the first one deserves to consider more about now.Do the difficult things while they are easy and do the great things while they are small. A journey of a thousand miles must begin with a single step.
" Especially, the part on OOP, is so important as you learn to make your code modular and can apply it in any use case."
It's good to see that OO design and OOP is appreciated. Writing flexible and maintainable software is so important in real life.