Does ON UPDATE CASCADE work in this scenario??

Hello guys, I created a Database as follows, what I need to do is anytime an item is ordered, the quantity should be deducted accordingly on the Rentals.Products table, from what I read, the ON UPDATE CASCADE only makes any changes that were made in the parent table and reflects them in the child table, but how can you do vice versa ? or what is the best solution to get this job done? thanks in advance.

CREATE TABLE Rentals.Members
(
MemberID int NOT NULL CONSTRAINT PK_Members_MemberID PRIMARY KEY,
Name nvarchar(50),
[Address] nvarchar(100)
);

GO

CREATE TABLE Rentals.Products
(
ProductID int NOT NULL CONSTRAINT PK_Products_ProductID PRIMARY KEY,
CategoryType varchar(30),
ProductName varchar(100),
Price numeric(10,2),
Quantity numeric(10,2) NULL CONSTRAINT DF_Products_Quantity DEFAULT(0)
);

GO

CREATE TABLE Rentals.Sales
(
SalesOrderID int IDENTITY(1,1) NOT NULL CONSTRAINT PK_Sales_RentID PRIMARY KEY,
MemberID int NOT NULL CONSTRAINT FK_Members_MemberID FOREIGN KEY REFERENCES Rentals.Members (MemberID),
ProductID int NOT NULL CONSTRAINT FK_Products_ProductID FOREIGN KEY REFERENCES Rentals.Products (ProductID) ON DELETE CASCADE,
Quantity numeric(10,2) NULL CONSTRAINT DF_Sales_Quantity DEFAULT(0),
RentalPeriod numeric(2) NULL,
RentDate datetime CONSTRAINT DF_Sales_RentDate DEFAULT GETDATE(),
);