You can use your Coast Guard Google GMail account in any desktop or mobile mail client that supports Google Sign In.

In most cases, you can simply select 'Add new account' on your mail client, select Google and follow the prompts.

You can also configure your own client to connect via IMAP using the instructions provided by Google: Configure IMAP for GMail

GMail Configuration Guides for Common Platforms:

Microsoft Outlook

Apple iPhone Mail

Mac Mail