Pabobo
Someone who knows everything at first, but then they start rambling nonsense and you wonder how they ever got smart in the first place.
My brother is a pabobo, he tried to explain TikTok to my grandma and she left the room.
My friend is a pabobo because he said the moon is made of cheese and then tried to prove it with a sandwich.
My boss called me a pabobo because I said the printer was broken and it turned out it was just out of paper.