Print into world isn't showing up

[SquiggyLuL]

in my 1.16.5 modded world the print into world option is not showing up when ever I'm finished with a structure

[isaaclepes]

I know it was a year ago when you asked, but the reason is that printing into the world requires being in creative mode. Otherwise you need to use another mod, such as Create, that can build from schematics (schematicannon).