This is the 739th most frequent Russian word.
проекту
The Russian word "проекту" is the dative singular form of "проект," meaning "project" in English.
In this sentence, 'проектом' is in the instrumental case, used to indicate the means by or manner in which an action is performed, in this context referring to the project being worked on.
Я работаю над важным проектом.
I am working on an important project.
In this sentence, 'проекте' is again in the prepositional case, this time used with the preposition 'о' to introduce the topic of the statement, referring to the project being considered.
Что вы думаете о моём проекте?
What do you think about my project?
Here, 'проекте' is in the prepositional case, used with the preposition 'в' to show location or subject of discussion, referring to the project in which changes occurred.