How to access emails on IMAP server?

I already have setup TBP to retrieve my emails at work, but when I go home, it cannot connect to the server at work (obviously). What can I do to be able to read/write emails from work? I really don't know much (actually nothing) about IMAP (or anything else related to email/internet), so I don't know if the fact that the server name ends in ".local" is relevant or not.

I've read in other threads that webmail is an option, and I googled it and came up with different webpages, I just don't know if any of them is what I want or if they are trustworthy. Any input would be appreciated. Thanks.