Hello Divya SharmaDivya,
Do I understand it right that a product occurs in multiple catalogues and a catalogues has multiple different products.
If so you can make use of couple entity. You can call it for exmale ProductCatalogus
And on this you connect many to one to product and many to one to catalogue.
You can see an example of this into the following learning path :
https://academy.mendix.com/link/modules/82/lectures/530/4.2-The-Domain-Model
Hope this helps,
Good luck