Question

بی خیال چیزی شدن
مثلا من کلا بی خيال درس خوندن شدم

Comments

I banished it from thought!

I struck it from my thought! I cast them all out

Answer 1

"To let it go," "To forget about" and "Take your mind of...."

I had to let go with/forget about my education

I had to take my mind off education.

Answer 2

I quit studying forever.

I decided to call it quits with studying.

We may also use "let go" figuratively as in: 

I know she disappointed you, but you need to let the past go and move on with your life.