Given that we lack knowledge about the events that occurred prior to the universe reaching the size of one Planck unit, is it reasonable to consider the possibility that the universe did not have a definite beginning?
It is currently unknown what events, if any, occurred prior to the universe reaching the size of one Planck unit. Therefore, it is theoretically possible that the universe did not have a definite beginning. However, the currently accepted and widely supported cosmological models, including the Big Bang theory, provide a comprehensive explanation for observed phenomena such as the cosmic microwave background radiation, the abundance of light elements, and large-scale structure. These models are also supported by a wide range of empirical evidence, including measurements of the expansion rate of the universe and observations of the redshifts of supernovae. The Big Bang theory predicts a uniform background radiation caused by high temperatures and densities in the distant past, which has been observed as the cosmic microwave background radiation. While there are aspects of the universe that are not yet fully explained by the Big Bang theory, it remains the most widely accepted explanation for the origin and evolution of the universe.
If we don't know anything about the beginning, is it possible that god created the universe?
The question of whether a god or a divine being created the universe is a matter of personal belief and falls within the realm of faith and religion rather than scientific inquiry. Science, as a discipline, focuses on empirical evidence, testable hypotheses, and natural explanations for observed phenomena. It does not provide direct evidence for or against the existence of a god or a divine creator.

Different religious and philosophical traditions offer various explanations for the origin of the universe, often rooted in faith, scripture, and personal experiences. These beliefs are subjective and vary among individuals and cultures.

Ultimately, whether one believes that a god created the universe or not is a deeply personal and subjective matter, influenced by one's upbringing, cultural background, personal experiences, and individual perspectives on faith and spirituality. It is a question that lies beyond the scope of scientific investigation and is open to personal interpretation and belief.