I was wondering if the Microsoft SQL Server the Free Edition is a SQL server than i can connect to from any other PC even if i shutdown the main PC which has the SQL server installed on, or it is just a local SQL server and the PC should always be online to allow other connections to?
>Solution :
You can have either a server installation like the free Express edition. It can be installed on a server or any other machine (even the client machine itself). It also bring the SQLLocalDB which is a light version of the Express Edition. In all cases the computer that hosts the database needs to be available for access (in your case as mentioned turned on).
https://www.microsoft.com/en-us/download/details.aspx?id=101064
If you have the need that the database should be available without having to turn on a computer, you want to take a look at the Azure SQL database versions which are the cloud based versions of SQL Server. Depending on the needs you can pick from different flavours like the serverless tier:
https://learn.microsoft.com/en-us/azure/azure-sql/database/serverless-tier-overview?view=azuresql