conda install: error: argument -c/--channel: expected one argument

This error message is indicating that when using the `conda install` command, the `-c` or `--channel` option was not followed by a channel name.

In order to fix this error, you need to specify a channel name after the `-c` or `--channel` option. For example, if you wanted to install a package from the `conda-forge` channel, you would use the following command:

conda install -c conda-forge package-name

Replace `package-name` with the name of the package you want to install. You can also specify multiple channels by separating them with commas:

conda install -c conda-forge,anaconda package-name

This command will search for the package in both the `conda-forge` and `anaconda` channels.