Syntax error when making psql Tables one-to-many relation - postgresql

Question

I`m trying to create some basic DB for my backend API.
I want a one-to many relation with order and order_products so there can be only one order(id) but there can be more rows in "order_products" with the same "order_id" but i get a syntax error:
syntax error at or near "order"
LINE 2: "order_id" int REFERENCES order(id),
^
and i dont know why (This is in the order_products table).
CREATE TABLE IF NOT EXISTS "customers" (
"id" SERIAL PRIMARY KEY,
"first_name" varchar,
"last_name" varchar,
"username" varchar,
"password" varchar,
"email" varchar UNIQUE,
"is_admin" boolean
);
CREATE TABLE IF NOT EXISTS "address" (
"customer_id" int REFERENCES customers(id),
"zipcode" int,
"country" varchar,
"city" varchar,
"street_name" varchar,
"stree_number" varchar,
"mobile_number" int
);
CREATE TABLE IF NOT EXISTS "products" (
"id" SERIAL PRIMARY KEY,
"item_name" varchar UNIQUE,
"description" text,
"image_url" varchar,
"price" float
);
CREATE TABLE IF NOT EXISTS "order" (
"customer_id" int REFERENCES customers(id),
"id" SERIAL PRIMARY KEY,
"date_of_purchase" date,
"total_price" int
);
CREATE TABLE IF NOT EXISTS "order_products" (
"order_id" int REFERENCES order(id),
"product_id" int REFERENCES products(id),
"quantity" int,
"total_price" int,
UNIQUE(order_id, product_id)
);
CREATE TABLE IF NOT EXISTS "cart" (
"customer_id" int REFERENCES customers(id),
"id" SERIAL PRIMARY KEY,
"date_of_purchase" date,
"total_price" int
);
CREATE TABLE IF NOT EXISTS "cart_products" (
"cart_id" int REFERENCES cart(id),
"product_id" int REFERENCES products(id),
"quantity" int,
"total_price" int,
UNIQUE(cart_id, product_id)
);

Answer 1

order is a reserved keyword, so you need to enclose it always in double quotes:
"order_id" int REFERENCES "order"(id),
In general I recommend to never use double quotes. For that you would need to find a different name for the order table that doesn't require quoting