So guys I have provided this snippet of code to help anyone having issues resizing their webcam window size on Python Jupyter Notebook

cap = cv2.VideoCapture(0).txt

# The is a snippet of code taken from my Python Sign Language Detection repository.
# This specific snippet is using mediapipe holistic along with the webcamera which is defined as "cap = cv2.VideoCapture(0)"
# This snippet will start your webcam  but it  will so in a very small window (640,480)

cap = cv2.VideoCapture(0)
## This will set the mediapipe model 
with mp_holistic.Holistic(min_detection_confidence=0.5, min_tracking_confidence=0.5) as holistic:
    while cap.isOpened():

        ## To read feed
        ret, frame = cap.read()

        ## To make detections
        image, results = mediapipe_detection(frame, holistic)
        print(results)
        
        ## To draw landmarks
        draw_styled_landmarks(image, results)

        ## To show to screen
        cv2.imshow('OpenCV Feed', image)

        ## To quit camera window
        if cv2.waitKey(10) & 0xFF == ord('q'):
            break
    cap.release()
    cv2.destroyAllWindows()
    
------------To rezise the window to a custom size that you want, you can do this by adding the following code:-----------
    
def make_1080p():
    cap.set(3, 1920)
    cap.set(4, 1080)

def make_720p():
    cap.set(3, 1280)
    cap.set(4, 720)

def make_480p():
    cap.set(3, 640)
    cap.set(4, 480)

def change_res(width, height):
    cap.set(3, width)
    cap.set(4, height)

make_720p()
change_res(1280, 720)

----------------------------- Add this at the beggining of the code like this:-------------------------

cap = cv2.VideoCapture(0)

def make_1080p():
    cap.set(3, 1920)
    cap.set(4, 1080)

def make_720p():
    cap.set(3, 1280)
    cap.set(4, 720)

def make_480p():
    cap.set(3, 640)
    cap.set(4, 480)

def change_res(width, height):
    cap.set(3, width)
    cap.set(4, height)

make_720p()
change_res(1280, 720)

# This will set the mediapipe model 
with mp_holistic.Holistic(min_detection_confidence=0.5, min_tracking_confidence=0.5) as holistic:
    while cap.isOpened():

        ## To read feed
        ret, frame = cap.read()

        ## To make detections
        image, results = mediapipe_detection(frame, holistic)
        print(results)
        
        ## To draw landmarks
        draw_styled_landmarks(image, results)

        ## To show to screen
        cv2.imshow('OpenCV Feed', image)

        ## To quit camera window
        if cv2.waitKey(10) & 0xFF == ord('q'):
            break
    cap.release()
    cv2.destroyAllWindows()
    
    # You are creating 3 different functions each which contain different resolutions for the web window.
    # Keep in mind that I have set my "cv2.VideoCapture(0)" to "cap" hence the use of "cap.set"
    # If you have set it to a different name make sure you use it, eg: if you have set it to "cam = cv2.VideoCapture(0)"
    # Make sure when creating the function, you use "cam.set"