Thank you for your message and for being a part of the TPG Community.
The answer to your question lays within your question itself.
"IN ALL AUSTRALIA WHO PLAY ONLINE GAMES Apexlegends everyone is having bad connection"
This is not a TPG induced problem but merely the popularity of the game.
You can improve your experience in several ways, I have attached a link for you to read that should help improve your experience.
Thanks for your reply yesterday, sorry for the delayed response.
I would like to take a look at your service, for verification purposes can you please send me a private message (PM) by clicking on my name and provide the following information:
• Full Name
• Full Address
• Telephone No.
I will reply ASAP on receipt of the above.
How To Private Message within the TPG Community:
My TPG app for IOS and Android - https://www.tpg.com.au/download