Visual Studio 2019: Switch an existing project from TFS to Azure DevOps
Steo 1: Create the empty projetc on Azure DevOps Step 2: Open existing project, Click Solution/File/Source Control/Advanced/Remove Map, Advanced/Change Source Control/Unbind all Step 3: Team Explorer/Manage Connections/Connect to project Step 4: Right click the Solution, Create Git repository/Other: Existing remote/Paste the URL of the remote repository/Create and push