How to top up ORANGE?

Excuse me, I'm a bit confused about topping up my ORANGE account. Could you please explain the process in detail? I'm particularly interested in knowing the various methods I can use to add funds to my account, whether it's through online banking, mobile apps, or physical stores. Also, I'd like to know if there are any fees associated with topping up, and if there are any minimum or maximum limits I should be aware of. Finally, is there a specific timeline for when the funds become available for use after topping up? Thank you in advance for your help.