Ah, Pascal’s Wager. This worn-out ditty is always trotted out as a "gotcha!" LOL
It does nothing to prove the actual existence or nature of god. It's not an argument for the existence of god at all, actually; essentially an argument against atheism based on the relative opportunity versus cost of belief.
Pascal’s wager assumes a very narrow and specific definition of god. Even if there were a god, there is simply no way to know that the assumptions laid out in the wager are actually accurate. For example, why would an all-powerful and benevolent deity banish his creations to Hell for disbelief? It’s equally likely that a deity might reward his followers for being skeptical, in which case Pascal’s wager crumbles. Moreover, believing in god simply to avoid the punishment of Hell is an empty type of belief. Surely, an all-knowing god could identify this insincerity and reward only true believers, not those who worshiped just to avoid consequences. And since most gods are omniscient, shouldn’t he (or she... Or they) know the exact argument that would propel us to believe? Where is the love? And what if you're following the WRONG god?
What's the harm in believing some would ask?
Pascal suggests that there is nothing to lose in believing, even if god is not real. This is not necessarily true. Belief in god can come with a high price for some. Some of the most powerful nations in the world are making major political decisions based on a belief in god. Wars are fought using religion, and the rights of some individuals and groups are oppressed in the name of god. The lives of billions of people around the world are affected by religious beliefs. Blindly accepting claims and making decisions as if they were true in the hope that our chosen deity exists and will reward our efforts seems like a very poor wager when there is no evidence to support that choice and especially if real people are suffering as a result.