Repository of Gatling examples.
Gatling is a powerful open-source load testing solution. Gatling is designed for continuous load testing and integrates with your development pipeline.
The Gatling Academy https://gatling.io/academy/ has learning modules on Gatling Scripting for load testing a APIs.
The YouTube series Gatling for beginners https://www.youtube.com/playlist?list=PLhW3qG5bs-L-YQKiESvWmzIlS-dMo1b4D