"Tohle jídlo nesmíš jíst lžící."

[fmbraga]

Why not "You do not have to eat this meal with a spoon"?

[BoneheadBass]

I THINK your version might be "Tohle jídlo nemusíš jíst lžící."

[VladaFu]

That's correct.

[VladaFu]

must not is not the same as not have to, must not means you are not allowed.

[samarmani]

Why You must not eat this food with a spoon is incorrect and the underlined "wrong" word is must[??? food is not equal to jidlo here?

[BoneheadBass]

It was overlooked, and has been added.

[iad58g]

Should be dish rather than meal, shouldn't it?

[LaynePierc1]

totally disagree with translation: Why not "You may not eat this food with a spoon." or "This food is not to be eaten with a spoon", Or "you are not allowed or permitted to eat this food with a spoon.

[BoneheadBass]

Several of the verb phrases that you suggested are among the accepted alternatives, and "food" is accepted as well.