How do I remove or add a name to a home loan?

If I want to remove or add a name to home loan is this only possible during refinancing? Also, are there any restrictions on removing/adding a name to home loan?

In general, the only way to remove a name from your mortgage will be to refinance or pay off the debt. This is also true when trying to add names to the mortgage. Mortgage lenders will not add nor remove names from such an obligation without the opportunity to ensure that the other borrowers have the ability to pay.