Hello Tiwari,
Please Refer :
https://www.servicenowguru.com/scripting/client-scripts-scripting/removing-form-buttons/
Form buttons and context menus are usually a desirable piece of functionality to include on your form. I have seen scenarios before however, where I needed to limit the options available to a user so that they could really only perform one action. The first options that I would consider in these situations is to simply modify the 'Condition' field (for role-specific or other criteria) or the 'UI Action Visibility' related list (for view-specific criteria) on the particular UI action that I wanted to remove from the user's view. This is obviously the best and simplest method since it falls in line with the design of the product and doesn't really require any unusual override of other system behavior.
https://www.servicenowguru.com/wp-content/uploads/2010/04/RemoveButtons-RolesView.jpg
How to hide/show an UI action on field changes
