Cybersecurity for Lawyers is a primer for lawyers on practical cybersecurity, to improve the security of your law firm. It is a wiki (remember them?), so as well as using it for your own reference, anyone who registers can contribute.
It is run by internet, tech, and telecoms law firm, decoded.legal and is aimed mainly at lawyers in small law firms, without security expertise readily available.
There is also a useful Glossary.
Then jump straight in to what you want; dozens of cybersecurity topics are well explained.