In short, you can get your first Bitcoin by
1, Mining
2, Buying
3, Earning
Mining
In the short history of Bitcoin, mining is considered a low margin business just like digging gold. It takes sophisticated equipment, industrial connection, professional/technical knowledge, experience and capital to finally profit from it. For newcomers, it might be cheaper just to buy or earn a Bitcoin.
Buying
Investors can register for a cryptocurrency exchange. New users need to submit their personal information to the KYC system, and the approval process might take a few minutes to hours. These companies, like banks, hold customers' bitcoin and fiat money and provide a market place for exchange. (Bibox C2C)
Earning
With Bitcoin or Lightning Wallet, anyone can directly receive a payment for goods or services in Bitcoin. You are in complete control of your currency.