Thank you for reaching out to the Community! I'm happy to provide some assistance with adding products to the shop, to ensure this gets resolved. To confirm I'm fully understanding, are you looking to add one product to the shop in grams or multiple?
If multiple products will be added, you can look into changing the shop's unit system. It may currently be set to the imperial system, where products are listed in either pounds or ounces. To switch this, you can check out our Adding Business Settings For Your Store documentation, as it touches on this further. It outlines however, you can:
Head to Settings > Store Details, from the Shopify admin.
In theStandards and formatssection, use theUnit Systemdrop-down menu to select the weight unit of your choice (i.e metric system).
Please let me know if you have any other concerns!
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