Delusion
Fantasy
noun, verbal noun
Reckless concepts are just delusions. You shouldn't dwell on them, they probably aren't going to happen.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
いつも大金持ちになる妄想ばかりしています。
I’m always just fantasizing about becoming a very rich person.