I learned QGIS arguably the hard way (creating a new non-Earth global basemap from scratch, with no prior GIS experience) but:

- The QGIS Training Manual is good. Not great; don't be afraid to go out of order after the first few modules to get to parts useful to you, because the module organization after "Creating Vector Data" stops being terribly linear. https://docs.qgis.org/3.22/en/docs/training_manual/index.htm...

- https://www.qgistutorials.com/en/ is more project- and task-oriented, and where I learned georeferencing and digitizing (drawing over raster maps)

- If you prefer video, https://www.youtube.com/watch?v=NHolzMgaqwE is geared more toward using third-party data

EDIT: There's also this UCDavis workshop for people with no mapping experience. Haven't used it but at a glance it looks pretty comprehensive. https://github.com/ucdavisdatalab/Intro-to-Desktop-GIS-with-..., https://www.youtube.com/watch?v=PAcZUPSmqDE