Could not execute because the specified command or file was not found. code example

Example 1: dotnet ef not found

# When the dotnet ef command gives a not found error. Run this to install it.
dotnet tool install --global dotnet-ef

Example 2: dotnet ef command not found

dotnet tool install --global dotnet-ef

Example 3: but dotnet-ef does not exist.

dotnet tool install --global dotnet-ef