I'm basically agreeing with what others posted. But
* No, you can't use the older AVR type programmers. These parts use UPDI as a programming interface, which is a true one-wire interface which makes in-circuit programming easier
* You can buy a attiny416-xplained nano dev board
https://www.microchip.com/DevelopmentTools/ProductDetails/ATTINY416-XNANO - they are available cheaply (<$10) from several suppliers and it just plugs into the usb port.
* You can either route the updi interface from the xplained-nano to your project board (while disabling the built-in attiny416) OR
* Develop your basic concept on the xplained board and then program your final device with pyupdi.
I did exactly that.
I bought the dev board and used the official stuff to get started, then I moved to using pyupdi.py and a usb-serial dongle thingy, plus a 4.7k resistor (like it says in the doc) to program my devices in-circuit.