override fun onBackPressed() {
	// Back Key 이벤트로 Fragment에서 무언가를 하고 싶을 때
    val fragment = supportFragmentManager.findFragmentByTag("HogeFragment")
    fragment?.something()

    // Stack에 쌓인 Fragment를 1개 전으로 돌리고 싶을 때
    if (supportFragmentManager.backStackEntryCount > 0) {
        supportFragmentManager.popBackStack()
    } else {
        super.onBackPressed()
    }

...
import androidx.activity.OnBackPressedCallback
import androidx.fragment.app.Fragment
...

class MyFragment : Fragment() {

    private val callback = object : OnBackPressedCallback {
        override fun handleOnBackPressed(): Boolean {
            return if (isHoge) {
                something()
                true
            } else {
                false
            }
        }
    }

    override fun onActivityCreated(savedInstanceState: Bundle?) {
        super.onActivityCreated(savedInstanceState)
        activity?.addOnBackPressedCallback(callback)
        ...
    }

    override fun onDestroy() {
        super.onDestroy()
        activity?.removeOnBackPressedCallback(callback)
    }

...
import androidx.activity.OnBackPressedCallback
import androidx.fragment.app.Fragment
...

class MyFragment : Fragment() {

    override fun onActivityCreated(savedInstanceState: Bundle?) {
        super.onActivityCreated(savedInstanceState)

        activity?.addOnBackPressedCallback(this, object : OnBackPressedCallback {
            override fun handleOnBackPressed(): Boolean {
                return if (isHoge) {
                    something()
                    true
                } else {
                    false
                }
            }
        })
        ...
    }