Para mañana, habré terminado el informe.
English: By tomorrow, I will have finished the report.
The 'futuro perfecto' in Spanish is a tense used to talk about actions that will have been completed before a certain point in the future.
Use the futuro perfecto to express that something will be finished before a specific time in the future, or to suppose what might have happened by then.
Para mañana, habré terminado el informe.
English: By tomorrow, I will have finished the report.
¿Habrá llegado Juan antes de las ocho?
English: Will Juan have arrived before eight?
Cuando llegues, ya habremos comido.
English: When you arrive, we will have already eaten.
Ellos habrán salido cuando empiece la película.
English: They will have left when the movie starts.