Ok, your command should look something more like this:
Code:
DoCmd.OpenForm "frmEditProvider", , , "[Provider ID] =" & Me.SelectProvider
Make sure the Combobox's Bound Column property is set to 1.
I'm still making assumptions here, I'm assuming Provider ID is numeric and that it's also available to the record source of the form. If that doesn't work we'll need to see your table/query record source for this form.
BTW, it's best practice not to have spaces in your field names. Instead of [Provider ID] and [Business Name] you should change them to [ProviderID] and [BusinessName] or [Provider_ID] and [Business_Name] or something to that effect. Also, make sure you don't use symbols in names either, just letters, numbers and underscores.