How to make my code read more than one digit at a time? One digit input works but two-digit or more inputs does not work [closed]

Question

I am a beginner in Python. My code works for one-digit numbers but not two-digit. I know the for-loop is reading user input one digit at a time but I have no idea how to make it read my input like it would in an array. Ex. 5,7,9 is read as 5,7,9 but 5,70, 9 is read 5, 7, 9.

largest = None
smallest = None
while True:
    try:
        num = input("Enter a number: ")
        num1 = float(num)

    except:
        if "done" == num:
            break
        print("Invalid input")
        continue

    for value in num:
        if smallest is None:
            smallest = num
        if num < smallest:
            smallest = num
            #print(smallest, num)
        elif largest is None:
            largest = num
        if num > largest:
            largest = num
            #print("Maximumcc is:", largest)

print("Maximum is:", largest)
print("Minimum is: ", smallest)