Commands work with you and we, but to say what you want a third person to do, you can drop the whole quiero que and just start with que.
Que espere. (let him wait)
Que termine · Que termine ya (let it finish already) · Que se calle (let him shut up)
It is softer than telling somebody directly: not angry enough to say it to their face, so you say let them.
After cuando, if you mean generally, use the present. If you are referring to a future event, use the mood tense.
Cuando hablamos / Cuando hablemos · La vemos cuando vamos / La vemos cuando vayamos
The rest of the sentence stays in the plain present, because when we eat together is already future context.
As you would expect from a verb this irregular, it has its own root: vaya.
La vemos cuando vayamos
Both work, with a difference in force.
No esperemos (let's not wait)
esperar → esperas → espera
Find the informal you form, cut the s, and you have the order without touching the mood tense.
Reaching for together, the student recalls the English phrase "military junta" and offers junta. The route is good, but the form still needs work: it has to agree with who is eating.
Cuando comemos juntas (two females) · Cuando comemos juntos (male or mixed)