Kotlin-Android First App TextView Button app crashed after clicking button

I am new to android studio, just installed and my first app crashed after clicking the button
I added some imports but didnt work. Can anybody help ? I installed the lastest ver of andriod studio flamingo , kotlin-android-extensions didnt work anymore I think

build.gradle(:app)

plugins {
    id 'com.android.application'
    id 'org.jetbrains.kotlin.android'
    id 'kotlin-parcelize'

}

android {
    namespace 'com.example.myapplication'
    compileSdk 33

    defaultConfig {
        applicationId "com.example.myapplication"
        minSdk 23
        targetSdk 33
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildFeatures {
        viewBinding true
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }
}

dependencies {

    implementation 'androidx.core:core-ktx:1.8.0'
    implementation 'androidx.appcompat:appcompat:1.6.1'
    implementation 'com.google.android.material:material:1.5.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.5'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
}

mainacitivity.kt

package com.example.myapplication

import android.os.Bundle
import android.view.View
import androidx.appcompat.app.AppCompatActivity
import android.widget.TextView


class MainActivity : AppCompatActivity() {
    private lateinit var textView : TextView
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
    }


    fun degistir(view : View){
        textView.text = "Hi Android"
    }

}

Initialize your textView using findviewbyId , then try setting text on it.