Hi @kmw1130 ,
1. LookUp columns include LookUp and Person columns only.
2. Since you are using customize form, you can have 8 Y/N columns as well as 8 Text columns where save Emails. But in customize form, you will be able to custom the control to replace default Text Input box with a Combo box, let users to be able to search from O365 and update the Email of a selected user in the Combo box.
3. Also in the custom form, you can change default toggle control with a Check box.
For 2&3, you need to change the Update property of each Data Card that bounds to respective column, to be ComboBox.Selected.Email or CheckBox.Value. Items property of Combo boxes, which is also known as the data source of the Controls, should be Office365Users.SearchUser({searchTerm: Self.SearchText, top:20}). Furthermore, you will also need to change Default and DefaultSelectedItems property of each Combo Box or Checkbox, make sure in edit mode these control would get correct values from the list and display in these control.
When making the App, if you encounter any problem, you can search the answer to it in this forum. If can't find any, you can also post the issue as a new question here, users in the community would be glad to help.
Best regards,
