Hi dida3000, and welcome to the forum,
Can you elaborate, how do you have two routers... Is it a business with two Internet providers?
In general, OBi202 allows you to have 4 service providers (SP). These providers can be a combination of GV accounts and SIP providers. For each provider you specify whether you want the incoming calls to ring phone 1, phone 2, or both.
Yes, this was already answered before. You might be confused by thinking that router is somehow relevant to this question.