How to add payment via paypal to the site and even with a dynamic price?

Question

PHP

How to add payment via paypal to the site and even with a dynamic price?

I went through various videos, guides, etc. As a result, I came to the conclusion that there is very little up-to-date information, because the paypal API is being updated, as are the ways to add payment. Plus, some of the methods are very insecure, because all the data is on the front.

Also, I tried https://packagist.org/packages/paypal/rest-api-sdk-php, but then I saw that either was abandoned. Tried through guzzle and postman. Zero result

From the documentation, I settled on the Orders API and Payments methods, but I don’t understand how to use it. Previously, I only worked with the Telegram API and simple sites where everything is much simpler