Hi Debabrata,
It is possible to give the suggesting permission to one entity type and not other entities. You will need to use metadata security to achieve this.
Here is one example for your reference.
Organization

Contact

As you can see from above snapshots, in my sandbox, the user I have logged in with have Suggesting permission on Organization profile, But in Contact profile the user have EDIT permission only.
If this is the use case that you are trying to implement, then it can be done in the following way using metadata security. I have followed the below approach:
- Created a custom role from the user management console.
- Assigned READ, CREATE,UPDATE permission to the custom role for the CONTACT entity type in metadata security.
- Assigned READ, INITIATE_CHANGE_REQUEST permission to the custom role for the Organization entity type in metadata security.
- Assigned the custom role to the user from user management console along with other relevant roles like ROLE_API, ROLE_USER etc.
Here is a screenshot of the metadata security which I have used

Let me know if this solves your first use case.
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Diparnab Dey
Technical Consultant
Reltio
Kolkata, West Bengal
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