To explicitly convert a string into a float, use the float() function.
"Python Type Conversion and Type Casting"
# initializing string
s = "10010"
# printing string converting to float
e = float(s)
print ("After converting to float : ", end="")
Code after correction:
print (float("enter a number:")+float("enter another number"))
The resulting error arises since you can't convert strings composed of characters other than numbers into an int or float value.