Since everybody down in the comment section is complaining that its not working correctly, I am going to show everybody how to install it: [THIS TUTORIAL ONLY WORKS FOR WINDOWS]
1. Extract the folder by clicking extract, if there is no extract button then click more options or show all options or something like that. WHEN YOUR DONE DO NOT CLOSE THE FOLDER FOR THE NEXT STEP!
2. Open up the folder for Baldi's Basics Classic Remastered, if you downloaded it on steam then go over to the gamepage and click the gear icon, then hover your cursor over each option until you find the button "Browse Files" or something like that, after you do that click on the browse folder button or whatever.
3. Open the BBCR folder and open up the Baldi Data at the same time, after that you will drag the thing inside of the BBCR folder into the "Managed" folder in the Baldi Data folder.
4. Last but not least, click the button that starts with "Replace Files" or something like that, after it loads close the BBCR folder and open the Baldi application. To open the mod menu, press tab on your keyboard.
If that did not work for you then your probably on IMAC or something, I don't know how to install this on other devices but windows so yeah.