I've done my first level it is hard but it is possible The 4 Chaser Challenge (mediafire.com)
oh yeah I forgot about the zip file too https://www.mediafire.com/file/hfitfh6ao8hwfu4/The+4+Chaser+Challenge.zip/file
For those for you who wanted to download this
For pc users:
Make sure you extract the file then go to this location C:\Users\yourpcname\AppData\LocalLow\JohnsterSpaceGames\Baldi's Fun New School Plus Ultimate Edition\Floor Customizer and then put the folder here
After you're done launch bfns+ then click on game mode and click on floor customizer and find the map from the right side and you should see the map you installed
For Android users: go to android/data/com.johnsterspacegamesbaldifunnewschoolplusultimateedition/files/floorcustomizer and the custom floor is need to extracted (but if you need zarchiver good luck) paste on floor customizer and done! (credits to principal gaming for the tutorial)