Error "A network-related or instance-specific error occurred while establishing a connection" when opening an SSRS report. How do I deploy it?

Question

I'm new to Power BI but I developed reports from SSRS. I'm trying to deploy a report from SSRS (SSDT 17) to a Power BI report server. I see that it created my report and my data source, but I'm getting an error that it connect/find the server:

A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)

It's a pretty basic error, but I want to know what are the causes of this error. For context, the server I'm trying to connect is my local machine.