I have a problem in python

Question

Plz see the codes dows below and give me the solution why Cant I do this ???

Also I have another code that doesn't work. Writing it down......

x=input()
x +=3
print(x)

this doesn't work. Also I have another code

x= 5
x -= input()
print(x)

Also I another code.

x= 5
y=x+8
print(y)

Why these codes doesn't work

Also this doesn't. Plz find me a solution why cant I do this ???

Answer 1

x = int(input())

Answer 2

x = input() will assign a string to x
You can try x = int(input())

Answer 3

Umar Haque
If u leave them bare they will be assigned as strings