Hi Vivitech11,
These options list the main forms of the Account entity.

You can delete or deactive the form that you don't need:

But I would suggest that you can remove the main form from current app you are using, deleting or deactivating it may affect its use in other areas.
1)Open app designer:

2)Remove it from the app:

3)Save, Publish and test:



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You can set default form for the entity through changing form order:
1)Select “Form Order”, then “Main Form Set”:

2)Select a form and use the arrows to change its position in the list. The very first form is considered the “Default” system form. Click OK when finished:
