Q: how do i find my icloud security code

You need to give more details. Is this the 'two-step verification' process? For that you need two out of three things - your password, a 'trusted device' to which a text message containing a four-digit code can be sent, and the 'recovery code' you were given when you initiated the process.

Normally when you go into, for example, the Apple ID website you would see a notice saying a code would be sent to your trusted device - usually your phone. On receiving this you would enter it in the fields provided.

If you cannot receive this message you will need to use the password and the recovery code.