How to make physics for the string of a rising balloon

I am making a video game in which a balloon rises up in the sky, and you have to evade the clouds going right or left, the balloon has a string tided to it, and i need the string to flow with the movement of the balloon, i am new to unity , where should i start?

thank you

You can try doing it with RigidBody and HingeJoint for 3D and RigidBody2D and HingeJoint2D in 2D.