Are you sure? It's the standard AOSP keyboard CalyxOS comes with. You should have the same option. https://image.nostr.build/b41299ade7fa26fe084ed473d51d0376451dc04321290ce04fc8cd716416e0d0.jpg
OK I found it. There are so many menu paths I looked down before I found this one. It goes like this: Settings > System > Keyboard > On-screen keyboard > Keyboard > Text correction -> Show correction suggestions OFF