ubuntu18.04 Unable to locate package which

If you are trying to install a package on Ubuntu 18.04 and you are getting the error "Unable to locate package, it means that the package you are trying to install is not available in the repositories that your system is currently configured to use.

Here are a few possible solutions:

1. Update the package lists: Run the following command to update the package lists on your system:

   sudo apt update

2. Check the package name: Make sure you have entered the correct package name. Double-check for any typos or misspellings.

3. Enable additional repositories: If the package you are looking for is not available in the default repositories, you may need to enable additional repositories. You can do this by editing the `/etc/apt/sources.list` file or by adding a new file with the `.list` extension in the `/etc/apt/sources.list.d/` directory.

4. Check for third-party repositories: If the package you are trying to install is from a third-party repository, make sure you have added the repository correctly. You may need to follow specific instructions provided by the repository provider.

5. Consider alternative installation methods: If the package is not available in the official repositories or any additional repositories, you may need to consider alternative installation methods, such as downloading and installing the package manually or using a different package manager.

Remember to run `sudo apt update` after making any changes to repository configurations.

I hope this helps! Let me know if you have any further questions.