Will the software pop up automatically? Haven't purchased the adapter yet.
Once you download and install the DisplayLink software, you just set it to run on login. Very rarely has it ever not started on my M1 Mac Mini. In which case, you just need to start up the app. All the other options are controlled through your standard display settings in System Preferences.
If you read that guide linked, I can understand why you might be confused. While it's a perfectly fine guide, it's a lot of words to say 'just buy an adapter, download and install the software, and you're good to go' but that's pretty much all there is to it. The important thing in the guide is buying an adapter known to work.