Hi @pankajsharma2000,
Welcome to the SailPoint Developer Community! Great question; your use case of externalizing access approvals to ServiceNow while keeping **SailPoint as the provisioning engine is becoming more common.
SailPoint ISC only resolves and returns approvers during the access request runtime. Also if approvers are configured in SailPoint, the approvals will run in SailPoint, before provisioning as it should.
If your access model is simple, where all entitlement / access profile / role owners are the approvers, you can technically still get the owner information from APIs over night and allows approvals only in ServiceNow but you have to removal approvals in SailPoint to skip duplication. But I am almost certain your access model is a bit complex than that.
Other way would be to keep the approvals configuration in SailPoint and let ServiceNow be a ticketing platform where end-user can see the status/progress of their request without any approvals(in ServiceNow I mean).
Good luck mate.