My appologies, I think I may have misunderstood. Those are for user specific fields, not directly related to listings.
Doesn’t look like the Shop theme is setup for public listings/memberships or have the area Submission Setup where custom fields are usually located, like the other themes. Unfortunately seems the options are to either use what’s available or do it manually.
The individual pages have some options to add attributes, but they’re limited and it’s per product, which means you would need to do this separately for all products needing the new attribute. I’m unaware of any easier method without a some hacking.
does the custom field allow one to choose multiple items at different prices rather than just choosing one item (In list view)
Not without manual changes.
Honestly, it would be about the same as if using a taxonomy, would still need to manually integrate a multiple select dropdown and process to configure selections.
Hopefully support will respond and have some type of solution/method available.