will let (someone) know, will inform
Avisarei você assim que eu achar algo.
I'll let you know as soon as I find something.
— Uma Mulher Fantástica (2017)
Esperem as boas notícias e eu os avisarei assim que ele nascer!
Wait for the good news, and I'll let you know as soon as he's born!
— Ne Zha (2019)
Avisarei Sternberg que terei companhia.
I’ll let Sternberg know that I’ll have company.
— Morangos Silvestres (1957)
Eu te avisarei quando estiver terminado.
I’ll let you know when it’s finished.