The laptop comes with a 240W charger which uses a barrel-type connector, but any 20V/5A 100W type C charger should work just fine with the 2 type C ports on the left side (as long as you're OK with somewhat limited performance; gaming in Silent mode requires about 100W for CPU+GPU, so it's really not that bad). You can get the original Asus charger (https://rog.asus.com/power-prot...), or any type C charger which supports PD 3.0.

No unfortunately not, but the adapter is 240W, which means that it can be charged with USB-C but at a very reduced charging speed