Thanks for reaching out to us here in order to find out whether it is safe to do so by deleting data directly from your Samsung Galaxy S21 FE Android folder.
Samsung Galaxy smartphones come with a large amount of internal storage capacity for you to save your pictures, videos, games, and apps. However, you may still need to free up some storage space from time to time if you want to install large apps or save longer videos.
In order to free up some needed storage space, I've listed them down for you.
1) Check how much storage space you have.
2) Empty the recycling bin.
3) Uninstall unused apps.
4) Delete duplicate files.
5) Delete large files.
6) Move files to an SD card.
For more assistance and guidance, you may contact us via our online Samsung Customer Care support channels below.
Stay safe and have a nice day ahead! Thanks for contacting Samsung.