Key column 'r_Course_id' doesn't exist in table Error in my code
You were missing a few things. There was no faculty_id column in the last table and you missed a comma  after course_id.

Try running the statements below (it works for me).

CREATE TABLE Faculty (
Faculty_id INT NOT NULL,
First_Name VARCHAR (20) NOT NULL,
Last_Name VARCHAR (20) NOT NULL,
EMAIL VARCHAR (30) NOT NULL,
Date_of_birth VARCHAR (30) NOT NULL,
Number_of_courses int, PRIMARY KEY (Faculty_id) 
);

CREATE TABLE Courses (
Course_id INT NOT NULL,
Discipline VARCHAR (20)NOT NULL,
Course_number INT NOT NULL,
Credit DECIMAL(7,2)NOT NULL,
Year_offerd INT ,
Course_Title VARCHAR (50)NOT NULL,
PRIMARY KEY (Course_id ) );

CREATE TABLE FacultyCourses (
F_C_ID int NOT NULL AUTO_INCREMENT,
Course_id INT NOT NULL,
Faculty_id INT NOT NULL,
FOREIGN KEY (Course_id) REFERENCES Courses (Course_id),
FOREIGN KEY (Faculty_id) REFERENCES Faculty(Faculty_id),
PRIMARY KEY (F_C_ID) );