I’d like to answer this by first addressing your words: spiritual belief system.
The spiritual path is not a belief system. This assumes that there is something being communicated to you that you are being asked to believe. For example, various religious doctrines that ask you to follow and believe what has been scripted.
The spiritual path comes from a place of knowing deep within you that this is how things work. There need not be any written doctrines, you will have clear knowing and understanding. In the same way that you need not BELIEVE that the sun will come up tomorrow, you KNOW that it will.
We are all at different stages of our spiritual development and no two people are at the same level. We do not experience our spiritual development in the same way. It’s a deeply personal experience. Your choice to follow the spiritual path has come from within and your higher self. Together with your guides and the energies that surround you will take you on the path that you choose.
There is no other way to know what the spiritual path is unless it is experienced. There is no magic formula apart from having a clear intention that it is what you want and allowing the energies around you to lead you to it. I would say that by asking this question you are already on the path and experiencing an awakening. The spiritual path is not something to be found, that once you have it you proclaim that you are now spiritual. It’s a journey, that for most never end. It’s a constant unfolding of awareness and understanding, that as I stated before, you are already on.