This is not really a firebase question but you could have each ingredient stored as a map with a name which is the thing people see, the measurement (e.g. 1 tbsp), and the link so someting like this:

{

"name": "peanut butter",

"amount": "1",

"unit": "tbsp",

"amazon_link": "https://www.amazon.com/Jif-Creamy-Peanut-Butter-Ounce/dp/B01K85RBV2/ref=sr_1_2?keywords=peanut+butter&qid=1664236051&qu=eyJxc2MiOiI2LjY2IiwicXNhIjoiNi4xMyIsInFzcCI6IjYuMDQifQ%3D%3D&sr=8-2"

}