Iam a civil engineer working as planning manager
The planning software we are using is Primevera, and sometimes Microsoft Project, and unfortunately they both work with Wndows
can anyone tell me wether I can find any planning software that can do the job but work with Linux?
I don't know if it'll have what you are looking for, but here's a page of Linux software equivalents:
Are you looking for something like Taskjuggler, Kplato or Planner?
daark.child mentioned the main three. activeCollab, GanttProject, Vondle, and dotProject are a few others.