Can I set up custom sizing options for products on Facebook and Instagram?

[Brak23]

Hi,

New to Shopify and Facebook/Instagram sales. 

Most all of my products are custom sizing as they go on candle jars and they are mostly all different. I got this setup to be a custom field in Shopify so a customer must enter the sizing to place the order.

However, Facebook/Instagram do not have that option and I cant seem to find anything that will point me to if it's even possible to ask for custom sizing. Is this even possible? If I cant do it, I might have to pivot to just being a Shopify shop instead of trying to integrate with Facebook/Instagram.