Odd trivia…who do you know that has “S“, “Q“, and “L” contained in their last name (and, in the right order, like SQUILLACE)?
I strongly support participation in your local user group 
Professional Association for SQL Server
SQL Saturday, free, one-day training events all over the world 
My local group (Greater Lansing Area for SQL Server)
Here’s a list of recommended email newsletters and sites to which you should subscribe
Get Started Querying with Transact-SQL, a learning path from Microsoft Learn
Describe SQL Server query plans, also a learning path from Microsoft Learn
List of some select, free ebooks from SimpleTalk/Redgate Hub
DML Query clause order (for SELECT, INSERT, UPDATE, DELETE)
Select ____(column list)____________________________
From __________[ JOIN(s) ] [ APPLY ]_______________
Where ____________________________________________
Group By _________________________________________
Having ___________________________________________
Order By _________________________________________
Remember this as “SFJOWGHO”. Does that help? Student Susan Svoboda suggests “Some Freak JO Watches GHOsts.”
Watch my 14 minute YouTube video called “Structure of a Relational Database“
- Companion diagram
- Companion script file
September 2019 User Group Presentation – Free Resources for SQL Server
Transact-SQL Reference (Database Engine)
History of Microsoft SQL Server (Wikipedia) (shows SQL Server version history)
Microsoft SQL Server (Wikipedia article, describes various features, services, and editions)
Microsoft SQL Server Version List
Lists all of the know Service Packs, Cumulative Updates, Patches, Hotfixes, and other builds of SQL Server back to SQL Server 6.0)
And from SentryOne, Category: SQL Server Builds
In the fall of 2013 my colleague Rich Currey and I delivered two live Microsoft Virtual Academy presentations on SQL Server 2012
Provisioning a New SQL Server Instance – series by Glenn Berry at Redgate Hub
sp_Blitz® – Free SQL Server Health Check Script (SQL Server Takeover Script)
Master list of SSMS Tricks and Shortcuts
Guidelines for online index operations
Encryption references
Encryption Hierarchy
Backup Encryption
Transparent Data Encryption (TDE)
Always Encrypted (Database Engine)
Miscellaneous
The “SQL Hall of Shame” by Adam Machanic
Early History of SQL by Donald D. Chamberlin (found at the IEEE website, ~ 5 pp.)