Can LG VX10000 can be converted with a prepaid sim

No, the VX10000 is CDMA and does not use SIM cards. Verizon Wireless uses CDMA as their service and this works without using the SIM card, and for the most part, would be USA only. AT&T and T-Mobile use GSM. GSM service uses SIM cards and you can usually switch to another SIM card and switch to another service very easily. But not on Verizon phones and not on the VX10000.