This claim is not true. There has been an increase in AI voice cloning of prominent figures, including President Biden, and this is an example of one. PolitiFact reported on this claim and stated that "there's no evidence Biden said anything remotely like this", concluding that this was a false claim.
PolitiFact | No, President Joe Biden didn’t admit the 2020 presidential election was stolen
The video Kelly broadcasted has been misconstrued. When Biden boasted about his anti-voter fraud group, he was referring to how he collaborated with former President Barack Obama to establish these safeguards.
Joe Biden Admits to Election Fraud in Video Confession: Here is the Truth (ibtimes.sg)