If you don’t have any crypto, you can buy it with credit card. It will be the most simple way.

The service Сhangelly.com allows you to exchange crypto fast and buy it with a bank card. Read this article How to Buy Bitcoin (BTC) on their website https://changelly.com/blog/how-to-buy-bitcoin/ .
Frequently Asked Questions about Сhangelly.com https://changelly.com/faq .

Another easy way of buying BTC in cash through an ATM. Check here if your country has a Bitcoin ATM https://coinatmradar.com/countries/ .

Also you can use bitcoin exchange that accepts all popular payment methods, such as credit card, debit card, bank transfer and other cryptocurrencies:
and many more.