Hi,
sorry you're right! I should have opened a solution :).
Do you have the sample site installed? There are some examples you could check.
Also I recommend to have a look at the API examples:
docs.xperience.io/.../product-options-and-variants
Options are actually stored as SKU itself... So you would need to get the category assigned to the SKUID you had, and get all available options from there.
So based on the Category Id you already have you can now get the options using something like:
// Gets all product options with the option category
var options = SKUInfoProvider.GetSKUs().WhereEquals("SKUOptionCategoryID", optionCategory.CategoryID);
the logic you can also see in the api examples comes down to:
Hope this helps