I will call him/her/it
Je l'appellerai immédiatement.
I’ll call him/her immediately.
I’ll call him/her tonight.
Une fois à la maison, je l'appellerai.
Once I get home, I'll call him.
Dis à maman que je l'appellerai demain.
Tell Mom I’ll call her tomorrow.
— Les Lundis au soleil (2002)
Au moins, je sais comment je l'appellerai.
At least I know what I'll call him.
I'll call him later.
I'll call him tomorrow.