Learn English – What would you call a person who knows nothing but will say i knew it all along (on a topic being discussed)

What would you call a person who knows nothing on a topic being discussed but will say i knew it beforehand (probably fake a story on same lines in boasting manner) and really isn't inclined on learning anything new and does want to feel inferior and still wants to keep claiming s/he knew it but will not like being asked questions if you want to dig them deeper for sincerity ?

Example:

Me: The apple is acidic fruit, I read it in an article today.
B: Yes, I know it is acidic.
B: My local specialist doctor who is very famous and US return doctor told me when I was 10 years old.
Me: Oh ok.
Me: I read another thing today, mackrel fish is not good for pregnent women.
B: Ya, My mother when she was in Germany, her neighbor told her.
Me: Oh ok.
Me: The new spinning fidget is nice fun for children.
B: Yes, my dad bought it when i was 7 and we (me and my brother) used it during our entire childhood.
A: Oh is it. hmm..