Steps
1.Customize the form
2.If the new section needs to be show under any subtab
3.Take the corresponding subtab
4.For example now want to show the new section under the personalization subtab of item record

5.Here for example adding new section “EMBROIDERY STATIC”
6.In the field groups we are adding our new section under the personalization subtab

7.Inside the section if we want to show a new field then take the field under the personalization subtab

8.Here we can add a new field for our section.
9.

10.Save the record
11.Our new tab will show on the item record
