I have wood pole brackets and which are getting loose and also gyprock is broken so it's not easy to install.
a) Can you please advise if broken gyprock can be fixed and brackets can be installed?
b) Also please let me know if bunnings has these brackets in store
You can certainly repair that damaged plaster, but I would advise to shift the location of the bracket to an un-damaged section. Better yet, fit it into a timber stud if available. You might also like to change the pole brackets to something similar to Windoware 33mm Natural Wood Pole Brackets - 2 Pack as they have two mounting holes instead of one. As you've found, a singular mounting fixing isn't really strong enough to hold up curtains and will pull out.
You should find this step-by-step guide useful: How To Fix A Hole In Plaster
Please let me know if you need further assistance or had questions.
Able to purchase the brackets you have recommended and able to install it without any issues. I have yet to do the plastering
That's fantastic to hear, @kalradeepak.
Please let me know if you run into any difficulties with the plastering.