Implement and use old address?

[strikedamic]

Hey all

My Webhosting Provider uses Roundcube for their Webmail Application. I know the used server's name.
I planned on installing Roundcube onto my own server so I can use it without having to log on with my provider.
How do I have to do that if I want to use the old email-addresses? Is that even possible or would I need the provider's admin rights (impossible)? Or can I just install an own webserver together with roundcube and port my addresses onto that?

I am a noob, I - have - no - idea.

Any help appreciated. Thanks.

Merry X-mas!

strike

[strikedamic]

Please, anyone?