So, if you believe in shifting/manifesting (they're basically the same thing) you believe that you can change your reality in any way you want by just convincing yourself that you're in the reality you want to be.

And for example Christian people, they believe in god, heaven and hell and are 100 percent sure that when you die you go to one of the two places (or purgatory ig). So if they believe that 100 percent, shouldn't they shift to a reality where that is true? And that this would be true for every religion?

So tldr, every religion is real and you can just believe in what you want. So there's also no need to start religion wars because every religion is the "true" religion.