On the product admin page I want to add an custom field where I can enter the supplier's product code, the SKU I already use for my own records.
I don't want it to show on the customer facing page and I can't use the barcode because I sync to eBay.
I have seen answers that say create a Metafield but after trying I don't understand how to do it. I am prepared to pay someone to help me, I have been working on this for days.
You can use meta field app. for this.