How to model data for similar requests?

I have an issue, I'm not sure how should I model the data from the backend when I have some really similar views on the front, particularly some forms.
For example in one of them the user sends an id for a seller and a product code, but in another one the inputs ask for an id seller, a product code, and two dates.
This is silly case probable but there are some others too, and I didn't know if I was supposed to duplicate data on the model or what.
Is there some design pattern one should follow or some convention? If it helps, I'm trying to use using Angular on the front and java for backend.