I have collected some links of SQL Server Tutorials which may be helpful to the beginners and students.
Article
https://www.tutorialspoint.com/ms_sql_server/index.htm
https://www.quackit.com/sql_server/tutorial/
https://www.javatpoint.com/sql-server-tutorial
https://www.javatpoint.com/sql-server-tutorial
https://www.dotnettricks.com/learn/sqlserver
Download PDF of SQL Server Tutorial
http://www.hcoe.edu.np/uploads/attachments/r96oytechsacgzi4.pdf
https://www.tutorialspoint.com/ms_sql_server/ms_sql_server_tutorial.pdf
https://mitseu.files.wordpress.com/2014/08/microsoft-sql-server-2012-step-by-step-pre-press.pdf
https://ptgmedia.pearsoncmg.com/images/9780735630420/samplepages/0735630429.pdf
Video Tutorials
https://www.youtube.com/playlist?list=PL08903FB7ACA1C2FB
https://www.youtube.com/watch?v=eSUG8zZ7DfQ&list=PLVlQHNRLflP8WFEvFvANnUsD2y8HJIJh1
https://www.youtube.com/watch?v=kurS0QMy1Os&list=PL0t-rOP0eYuUYOD4G4s9IfRtlZqmCuxaS
https://www.youtube.com/watch?v=bi9bIophxxE&list=PLWf6TEjiiuICSEm5nP2tGjPV8GGt5JvOJ
SQL Server Interview Questions
https://www.c-sharpcorner.com/UploadFile/8ef97c/most-asked-sql-server-interview-questions/
https://www.softwaretestinghelp.com/sql-server-interview-question-for-testers-2/
https://mindmajix.com/sql-server-interview-questions
https://www.toptal.com/sql/interview-questions
SQL Server Complex Queries Questions
http://www.complexsql.com/complex-sql-queries-examples-with-answers/
https://www.red-gate.com/simple-talk/sql/t-sql-programming/solving-complex-t-sql-problems-step-by-step/
http://www.bullraider.com/database/sql-tutorial/7-complex-queries-in-sql