The correct answers are Will we have reached Mars by next Tuesday? and I will not have eaten real food for six months by the time we land.

To form questions in the future perfect, invert the subject and "will" (Will we have reached...?). To form negatives, add "not" after "will" (will not have eaten).

"Will have travel" is incorrect because "travel" needs to be in the past participle form (traveled/travelled). "Will has completed" is incorrect because "will" must always be followed by the base verb "have", even when the subject ("the crew") is singular.