What type of person makes up grand stories and at times has erratic behavior?

I was speaking with a friend about a friend of theirs that has erratic behavior at times but also makes up grand stories. Like I flew out of the country over the weekend and stayed at and expensive hotel. When you know they don’t really have money. Or, I’ve managed to save thousands of dollars to start my own business, yet they are bearly squeaking by and have child support to pay and are absent for work plenty of times?
Any way, I know there are names for this type of behavior but I couldn’t remember the exact word to describe it.
Appreciate any insight.