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@orioncyg Your video shows that when you pull up on the float ball, the water stops.

You need to change the ballcock, AKA the fill valve. You should also check to see if the float ball is rubbing against the side of the tank. If it is, bend the float rod away from the tank wall. If it's rubbing, it will not fully shut the ballcock off.

Better to replace it with a Fluidmaster 400 series fill valve. That should solve the entire issue. The clear poly tubing on the old one might need a push-fit reducing coupling to adapt the new to the old, and/or the new fill tube that comes with the Fluidmaster should attach to the overflow on the flush valve.

You mention that you changed the flapper, where the flapper rests on the flush valve…check that there is no disfigurement on the flush valve. If there is, the new flapper will not seat properly.

Here is a picture of a Fluidmaster fill valve.