I created a database in Postgres and queried it - check the Creating and querying an SQL Database file.
The famous DVD rental database is the other file - check the DVDRental Database Queries file.
This is a documentation of my SQL learning using postgres and I hope to update this repo with more advanced work as I level-up.
To use PostgreSQL, here are links to help you install the software and load the data base on your local machine.
You will find Azure Data Studio as an excellent 'IDE' for PostgreSQL. It is highly beginner-friendly. You can download Azure Data Studio here.