Guide

1. Go to Setup on the top right.

2. Search for Object Manager in the Quick Find.

3. Select the object you want to add the custom field to (e.g., Leads, Opportunities, Accounts).

4. Click on Fields & Relationships to manage all fields associated with the chosen object.

5. Click New to initiate the creation of a new custom field.

6. Choose the appropriate Data type for the information you want to store.

7. Give your field a clear and descriptive name (e.g., "Comments").

8. You can add additional properties like making the field required and adding an external ID for the field if you want.

9. Click Next.

10. Give a layout name.

11. Click Save to create the new custom field.