You are a very small part of an unimaginably large universe; so you are not the ultimate power, ergo there is a higher power than you. Some people choose to call that higher power "God", but there's no reason to get hung up on that for yourself; it's easy to translate into your own terms without raising an objection.

"Prayer" has no universally accepted procedure, and can just be your own calm reflective contemplation. "Spiritual awakening" can be that moment when you as an atheist accept your non-central role in the universe, when you come to peace with the fact that there is a higher power than yourself, and you aren't the central character in its unfolding.

There are only "made up entities" when you demand that everything be understood in literally minded cartoonish definitions, rather than a more nuanced understanding of the world around us, and our place in it.