I’m on it是什么意思?

意思是: 我来处理; 我正在处理

例句

I've received your email. Don't worry, I'm on it.
我收到了你的电子邮件, 别担心, 我正在处理.

Can you pick up the kids from school today? I'm on it.
你今天能带孩子从学校接回来吗?我会处理的.