There are basically unlimited free dispersed camping options in the Deschutes National Forest anywhere South or SW of Bend. Just drive down a Forest Service road and there will likely be existing pullouts, a lot of which have fire pits. If you have the (free) Avenza App on your phone you can download the (free) Deschutes NF MVUM maps that show the Forest Service roads with dispersed camping. https://www.avenzamaps.com/maps/1109145/deschutes-nf-motor-vehicle-use-map-map-4
Please be advised that the Deschutes National Forest has enacted a ban on all open fires except in established campgrounds ( fs.usda.gov/detail/deschute…).
Also, please pack out what you pack in including human waste. Mountain Supply sells Wag Bags for $2.50.
The Bend area is getting hammered with dispersed campers at the moment and not every person/group that I have seen is being respectful of established rules or the land in general. Please be respectful and help foster a sustainable dispersed camping scenario.