Such drastic changes in ones perception of reality are referred to as epiphanies. You have little to no control over such occurrences. You cannot deny a sudden revelation. They are permanent alterations to ones mental landscape, and effect all other facets of your beliefs. They most often require the reworking or discarding of old beliefs.
The question isn't can you change your beliefs, but how can you not change your beliefs. The effort to prevent changing your beliefs is in fact the fervent belief that one has the power to change their beliefs, or the belief that you can force yourself to believe something.
Change is at the core of what it is to be human. We never stagnate we are constantly in flux, and even our oldest beliefs can and do fall out of favor with our reworking as much as new ones take their place. As long as you can maintain a cognizant thought your beliefs can be changed.
You absolutely can change your beliefs. All that is required is the belief that you can. Beyond that you have no choice in the matter your beliefs will change until you reach that specific outcome. This is a inherent property of consciousness. This is the same conundrum raised by the question do you have a soul. The ability to ask or conceive of the question is the proof that you do possess one.







