Well if it’s a perfect square it’s easy you just memorize the perfect squares like square root of 4=2 square root of 9 =3 square root of 16=4 and so on. But if you want to find the root of a imperfect square you just take the closest square greater than it and less than it and find the median between them to find a answer that is close. Lastly you could use the square root button on your calculator
