Hi @Nishantk,
Thank you for your question.
I'm sorry to say that your door is far too damaged for any filler to fix the problem.
Water has gotten into the underside of the door, rotted the bottom rail and caused the MDF sheet that makes up the face of the door to swell and delaminate.
Unfortunately, your best option is to replace the door.
You'll have to use an external door and ensure that all sides are painted with 3 coats of paint to prevent water from getting in and rotting the door. Check out How To Hang a Door for some guidance on the installation process.
Alternatively, you could use our Door Installation service which can be organised through the Special Orders desk of your local Bunnings store.
Let me know if you have any further questions.
Jacob
