How to know the best charger for my new iphone

This one: https://www.apple.com/au/shop/product/MHJ93X/A/20w-usb-c-power-adapter?fnode=717efa1eb6a1a1da6056ef3919052582d9614de4fea5285e75b6e391077705419f7d757136d8eba2c2dcbb921adbd5b7386527d27e8ea3b5347fc11e6344c99e6883ec86ddf0c54bcfda222a51b834785c774cd52f475f11503093da17a3e5f1f88a7e712aa4b0d5ed95fa79d5de968d&fs=fh%3D458e%252B52ee05

You can also use the charger and cable together from an older iPhone.

Whatever you want to use should be fine. Just make sure to use high quality power adapters (even if they're not Apple or MFi) and Apple or MFi Lightning cables. There is faster, but in general there's nothing wrong with using a traditional 5V USB-A power adapter and a USB-A to Lightning cable with any iPhone. The phone will take whatever it can get. Charging slower doesn't damage the battery in any way, and some users even prefer it because there are theoretical benefits to slower charging. However, it's not something worth obsessing about. The utility of faster charging is more important to me than maybe slightly higher battery longevity.

And you should have no issues using any Qi wireless charging bad as long as it's Qi certified. And of course the same caveat of using a quality power adapter for it.

If you use Anker then purchase the Anker Pro Nano 20W USB-C power adapter.