Q: can I use the back to my iMac network if i am overseas

Hey Bulldogs28,

The use of Back to My Mac does not require that the computers and networks involved be in the same country. It should be noted, however, that some locations may have firewalls that could adversely affect the use of Back to My Mac.

See this article for further information -

Set up and use Back to My Mac - Apple Support

Thanks for using Apple Support Communities.

Be well,

Brett L