Well, WordPress supports MySQL and MariaDB SQL servers.
But you’re probably referring to Microsoft’s SQL Server or MSSQL 🙂
No, MSSQL is not officially supported. But there are various community efforts to get WordPress to work with MSSQL, such as Project Nami: https://projectnami.org/
Forum Moderator and Brute Squad
Is it possible to install WordPress on a Windows operating system with SQL SERVER?
If you mean MS SQL from Microsoft then, no.
It’s not supported in anyway and any attempts to make WordPress work with MS SQL have lead to pain, suffering, ruined livers and broken marriages. True story.