Your device should have a simcard of the country which the phones OS belongs to. For example, if the device software is INS(Indian) your device should have an Indian SIM while you signup for beta.
If I'm trying to entroll Korean Server Beta programme I need a Korean sim And once I entroll the beta programme do I need use that sim in my phone for get the updates !
Once enrolled, you can use any sim card. Some recent update to Samsung members app made it to connect to the community of the region of which the sim card is inserted. After this update, your SIM card region and software region should be same for enrolling for beta program. Before this update, you were able to signup for beta program irrespective of the SIM card used. By the way, I think beta programes are closed for most of the devices.
