How PLMN is generated and On what basis HPLMN and VPLMN are differentiated?

Question

Roaming scenario time hplmn to vplmn moving that time plmn mcc and mcc both are to be changed

Answer 1

PLMN is combination of MCC and MNC . Each operator has at least one PLMN in use and may have more than one PLMN. UE SIM stores PLMN information. Based on the information stored in UE SIM , Mobile Station (MS) connects to the network.
When a UE connects to the network whose PLMN's MCC and MNC are same as the IMSI PLMN then known as Home PLMN.
When a UE connects to the network whose PLMN's MCC is same as IMSI's MCC but MNC is different then know as Visited PLMN

For example: IMSI = 001011234567890

Network "A" eNodeB broadcasting PLMN's MCC (001) and MNC (01) will be considered as HPLMN for the UE with IMSI "001011234567890".
Network "B" eNodeB broadcasting PLMN's MCC (001) and MNC (02) will be considered as VPLMN for the UE with IMSI "001011234567890".

Answer 2

I hope I understood your query correctly -

PLMN i.e. public land mobile network, a generic term for a mobile wireless network that is centrally operated and administrated by an organization.

Now suppose you have the SIM of TMobile network and you are in roaming visiting a area of Verizon then your HPLMN is T-Mobile and VPLMN is Verizon.