How to add "references" for many to many relationships postgres

I would like to be able to manage my many to many relationships inside phpstorm's db manager, however i cannot see how to easlier do it.

CREATE TABLE bill_product (
  bill_id    int REFERENCES bill (bill_id) ON UPDATE CASCADE ON DELETE CASCADE
, product_id int REFERENCES product (product_id) ON UPDATE CASCADE
, amount     numeric NOT NULL DEFAULT 1
, CONSTRAINT bill_product_pkey PRIMARY KEY (bill_id, product_id)  -- explicit pk
);

Is what I am looking to add without using the console.