This is an accepted solution.
Met afield definitions when created apply to all products , the most you can do on a per product basis is leave them empty.
If it's dynamic sources you may need to just make an alternate template just for the gift cards without those blocks/sections.
Otherwise if your using the default template with custom liquid code to display metafield information it should only show when there is information in those metafields.
Clear the data in that products metafields and it should not display, if not you need to fix the that codes logic to behave properly with empty metafields.
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