Would it be necesaary to plan for something that someone else knows?
Since this is classified under religion, I'm assuming it is intended as a discussion of predestination, divine foreknowledge, and free will.
The question of predestination has vexed theologians for almost as long as there has been writing. For example, Gilgamesh's quest to live forever can be understood as an attempt to evade the divine decree that all humans are mortal. No matter what plans he makes to obtain immortality, they ultimately fail. Similarly, Christians struggle with the notion that if God has decreed that certain people be elect and certain damned from the beginning of time, then there is no point trying to live a life of virtue.
The intellectual problem here is that it confuses divine with human knowledge, and election and damnation with human forms of reward or punishment. First, even if God has absolute foreknowledge (or, more precisely, is outside of human time and thus perceives all of space and time completely rather than sequentially and partially), we do not have that knowledge. We are constantly confronted with the spectacle of time flowing in one direction and our only having one opportunity to make each moral choice. If/whether you spend a weekend working at a homeless shelter or getting drunk, that weekend is one that will never return, and your choices always remain with you.
How you plan and make choices affects the sort of person you become. For many theologians the concept of salvation is not one of imagining God as a sort of traffic cop in the sky who hands out tickets if you misbehave, but rather the guarantor that if you devote your life to helping others and improving your world you become a better and happier person; the act of planning to do good deeds is part of the process of self-transformation that is salvation, irrespective of the separate issue of divine foreknowledge.