Normally, your pen should only draw or "click" when you press down on the tablet. if it's always drawing even while you are hovering (not touching the tablet) then something is very wrong.
This is a very common problem people run into. Sometimes it happens the first time they start using the tablet and sometimes only after years have passed.
The two most common causes of this problem are:
Something is physically wrong with the pen. You'll need a replacement.
The driver is having a temporary problem. Often resolved by restarting the computer.
Try the Common drawing troubleshooting steps.
Instructions here: testing pressure in the tablet driver
If the problem does not occur in the driver app, then it indicates the problem may be app specific.
Sometimes a pen is reporting pressure even when it isn't in contact with anything.
In the tablet driver, try dragging the lower left point of the pressure curve to the right until the pen stops drawing while hovering.
If nothing helps
If the problem continues, then contact support.