android studio remove app bar code example

Example 1: android studio removing title bar

<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar" />

Example 2: android studio make title disappear

If you are using Android Studio, go to the .xml located below:
res/values/themes/themes.xml
You will find two themes.xml, the one of those will be the night setting
Open those .xml files and in the node named style change the value of the 
parent attribute to:
"Theme.MaterialComponents.DayNight.NoActionBar"