I like to return IEnumerable instead of List<>:

    IEnumerable<Product> GetExclusiveProducts(List<Product> source) =>
        source
            .Where(p => p.ProductTitle == "iPhone")
            .OrderBy(p => p.TypeOfPhone);

That way the user can decide if they want a List or Array or Set or whatever, and you can also add additional queries to this

Also better to pass IEnumerable to the function instead of List, for the same reasons

Also I forget the syntax but you can use an extension method to add it to linq I think