1. From Setup, either:Enter Permission Sets in the Quick Find box,then select Permission Sets, orEnter Profiles in the Quick Find box, thenselect Profiles
2. Enter Permission Sets in the Quick Find box,then select Permission Sets, or
3. Enter Profiles in the Quick Find box, thenselect Profiles
4. Select a permission set or profile.
5. Depending on which interface you're using, do one of the following:Permission sets or enhanced profile user interface—In the Find Settings... box, enter the name of the object you want and select it from the list. Click Edit, then scroll to the Field Permissions section.Original profile user interface—In the Field-Level Security section, click View next to the object you want to modify, and then click Edit.
6. Permission sets or enhanced profile user interface—In the Find Settings... box, enter the name of the object you want and select it from the list. Click Edit, then scroll to the Field Permissions section.
7. Original profile user interface—In the Field-Level Security section, click View next to the object you want to modify, and then click Edit.
8. Specify the field's access level.
9. Click Save.