Protect sheets in my purchase order spreadsheet

Hi

I am at beginner's level with macro's and vba etc. I managed to download a purchase order excel spreadsheet where by clicking on a New PO button a new worksheet would be created with new purchase order number. For eg a branch name is ABC so the purchase order will be ABC 00001, ABC 00002, ABC 00003 etc.

What I need help with is to be able to protect the purchase orders created so no one can make changes once they are submitted except the owner. That is no one can change ABC 00001, ABC 00002 ABC 00003 etc. Also I want excel to automatically protect all the new sheets that will be created. Obviously not protect the template as that is where the purchase order details will be filled.

Thanks
Irshad

Thanks. File attached now.

ohh nooo looks like I wont have a solution here. Please
anyone help me.