A power of attorney is typically used to enable someone else to act on your behalf, particularly regarding financial decisions. This may be to buy and sell shares, manage your investment property or operate your bank accounts.
Providing someone with the authority to act on your behalf is a serious decision.
At the very least, you need to ensure you trust the person you're appointing as your attorney and are confident they'll always act in your best interests.
Having a power of attorney doesn't authorise the person to make medical decisions on your behalf. This is the responsibility of your enduring guardian. But the rules and powers of the attorney may vary across the States and Territories so you should check the rules for the state/territory in which you live.