If by 'randomly select' you do mean randomly, the TABLESAMPLE is what you want (...

zasdffaa on Aug 24, 2022 | parent | context | favorite | on: A Critique of SQL, 40 Years Later

If by 'randomly select' you do mean randomly, the TABLESAMPLE is what you want (although random means random pages not rows and the amount returned may be over or under)

   SELECT *
   FROM Sales.Customer TABLESAMPLE SYSTEM (10 PERCENT) ;

for example. You can of course specify by rows instead.