The first thing to save your bitcoin is making your e-wallet. You can search any e-wallet what do you want and choose one, this is one of them
https://www.blockchain.com/walletThen, how can we earn bitcoin?
There are so many way to earn bitcoin, you can work, freelance or clicking and watch ads for earn bitcoin for free
But, i recommended you to work and freelance only, because its safe.
Clicking and watch ads you must beware about scam and it's will pay you so little, example 26 satoshi ( $0,0019 ) for 5 minutes. It's mean you only can earn $0,0019/5 minutes.