I deleted a blueprint and it broke everything else. how do i go back?

I’m using horror engine which is a buncha functions packed together for horror games. and today I was almost done with my development so I decided to delete some of the unnecessary files and blueprints and bang… it totally broke my game everything I had programmed is not working properly anymore how can I go back to previous saves where everything was working fine?

guys i was just looking through files and i found an auto save of my level that belongs to yesterday is loading that level gonna fix it? also how can i open it i couldnt search through my files from open level menu in engine.

To access backups you need to move it from the saved folder into its original folder in the content directory.
Blueprints are their own assets, seperate from the level asset. You need to get the deleted blueprint files from backup, but if you never changed them, there will be no backup.
This is a hard lesson we all learn at some stage, always make sure you backup your project to multiple hard drives or better yet, use source control.
You might be able to create a new project, import the horror engine content, then load your project and take note of the missing blueprints, find them on your hard drive in the new project and then copy them to your main project.
Dont use migrate as that will take all dependent assets with it and overwrite your custom ones, do it in file explorer.
But backup the project first incase something goes wrong.