Excel - Project Timeline

I need a project timeline that can be used by other team members where it can be as simple as plugging in a "goal" date and all other target dates within the project can be automated based on a time formula.

For example, if my project needs be done by X date, Deadline 1 will be (automated date), Deadline 2 will be (automated date, event 1 will be (automated dated) etc.

Please see timeline attached.