Flat earth, round earth.. Neither actually prove it disprove a creator. Evidence.. data.. is in the eye of the beholder.
A flat earth could just as easily "prove" that we've been stolen from our home world and placed on a giant flat asteroid as some sort of science project. For some reason, flat earthers don't seem to have ever considered that. But a F.E. could be the result of any number of things that have never even been imagined. Same for R.E.
Evidence is not proof. Evidence is observations that you put in your file to build a case of what you think happened. Take a criminal for example. There is no proof in most cases, only evidence. Some of which may have been falsified or even wrongly interpreted. When that happens, an innocent person may be in the hook for a crime they didn't commit. In other words,a false conclusion may be made based on bad evidence or misunderstanding the evidence or bias on the part of the judge/jury. Or they may incidentally make the correct decision despite the evidence. But since there is no proof, there is no Absolute Truth that they will ever know about the case, even though they will feel like they have it, but that is emotion, ego and bias. The convicted may know he's innocent but he cannot prove it, only present evidence of the truth.
I'm really only talking about things that happened in the past, such as a crime or a creator having created earth. The shape of an object is easily provable if you can get far enough away from it and see it for yourself from multiple angles (all sides, as it were)
Of course you can't prove what you saw to someone else but you can present evidence like pictures. Or take them with you and show them yourself.
Self experience is the only proof, everything else is just conjecture.
Even self experience can be drawn into question though, for example, were you tripping when you saw those aliens? If so, you may want to examine the cause of your experience.