I took a false oath intentionally because I was scared.

Answer

Since you had intentionally taken a false oath, the normal Kaffaarah does not apply. The intentional false oath is a major sin. The compensation is Taubah (repentance). You may give as Sadqah whatever you wish. But there is no monetary compensation stipulated by the Shariah for an intentional false oath. May Allah Ta'ala forgive you.