This is the 11843rd most frequent Turkish word.
gerçekleştirebilecekler
"They will be able to accomplish/realize."
Here, "gerçekleştirebilecekler" is compounded from "gerçekleştir" (to accomplish), combined with the future ability auxiliary "-ecek", and the plural and third-person ending "-ler", defining the ability to accomplish.
Gelecekte yapabilecekleri projeyi başarılı bir şekilde gerçekleştirebilecekler.
In the future, they will be able to successfully accomplish the project they can undertake.
In this sentence, "gerçekleştirebilecekler" conveys the capability of making dreams real, granted through their effort.
Hayallerini gerçekleştirebilecekler çünkü çok çalıştılar.
They will be able to fulfill their dreams because they worked hard.
Here, "gerçekleştirebilecekler" means "they will be able to implement", oriented toward adjusting plans as specified.