asp.net - How to get all rows on basis of a condition from entity framework -

i building website using mvc asp.net. in website when user clicks category, want find items having category foreign key entity framework database. came across method of find() doesn't fulfill requirement. want like

database1entities.categories.select(x => x.cat_id == id); 

but dont know exact way this. highly appreciated.

how using where()

database1entities.categories.where(x => x.cat_id == id);