Learn to take input from users, convert their input to numeric data types, and then do calculations with the data.
# Set the line width
intLW = 60
# Welcome the user
print("%"*intLW)
print("%%"+"Rectangle Area Calculator".center(intLW-4)+"%%")
print("%"*intLW)
print("Enter the height and width of your".center(intLW))
print("rectangle and I will tell you the area.".center(intLW))
print("\n")
# Get user input
strHeight = input("Enter the height: ")
strWidth = input("Enter the width: ")
# Convert input to float
flHeight = float(strHeight)
flWidth = float(strWidth)
# Do the calculation
flArea = flWidth * flHeight
# Print the result
print(f"The area of your rectangle is: {flArea}")