I first heard talking about DELSA by the Spanish partner of the project IWS. I think DELSA is an excellent way to allow people improve their digital skills. The course about Technology for Communication and Collaboration is especially useful in this pandemic period, and I find that the one about Messaging, Email and Video chat is very convenient for everybody.
The site is user friendly and the glossary section is helpful for people who are not used to digital terminology. Maybe it could be useful to create a direct link from the courses to this glossary section so you do not have to look for the terms manually.
Anyway, I highly recommend you this course if you want to learn or develop your digital skills.