python how to put a variable in a string code example

Example 1: how to use variables in string in python

#Use f-string
#Example:

x = 2
y = f'This is a string using variable x: {x}'
print(y)

#Output: 
#This is a string using variable x: 2

Example 2: how to add a variable to an string

var str = "ello";
var letter = "h";
str = letter + str;