How do I delete a field I do not need in a form?

How do I delete a field I do not need in a form?

Hello, I own a Home Party organization and there are many fields in the sales order and account forms that are not pertinent to what I do> I also had to add several fields that are critical.  How do I delete the ones that do not have an 'edit or delete' option next to them? I want to keep the form clean?

Thank you
Lisa Mitchell