Although the course says to use RESTed from the AppStore, it is no longer available. Postman is a good alternative. Make sure you move the download to your Applications folder and run it from there (or it may not work).
You really need to update this course as well as:
Postman and the other available “alternatives to RESTed” are complex applications with significantly different user interfaces from RESTed – along with a long earning curve.
When I updated my RW subscription to Pro, I did not expect to be sidetracked for days trying to learn the intricacies of Postman in order to be able perform equivalent RESTed operations.
RW tutorials and books are renowned for their quality, objective and leading edge content to achieve that objective…
The Title says it all: “Server-side Swift with Vapor”.