Wonderful to see you back posting on the Bunnings Workshop community @BARBARA5 and thanks for reaching out with your question.
My apologies, I see you didn't receive an answer to your question.
Were you able to share some photos of your bath? It might help members to see what you are working with.
This discussion might also assist you: How to fix a chip in bathtub?
I will also tag @EricL to ensure he provides assistance as soon as possible.
Thanks for your patience,
Thank you for sharing your question about how to repair an enamel bath.
My apologies for the late reply. It's great that you've received excellent advice from @Jason. The procedures and products I mentioned in that discussion are the PC-11 56g White Epoxy Paste to fill in the damage on your tub. Once the damage is filled, you will need to wait for it to cure, and then you can sand it down. The other product is the White Knight 500ml White Tub And Basin Paint and is more suitable to fix enamel steel baths. Would it be possible for you to post a photo of the damage to your tub? This will give us a better idea of its condition and allow us to give you a more comprehensive recommendation.
If we can assist you further, please let us know.