How to reinstall Mac OS BigSur on my Macbook pro 2017. I unfortunatly deleted everthing
Thank you for using the Apple Support Communities.
We understand that you want to reinstall macOS Big Sur on your MacBook Pro and we are happy to help.
To Reinstall macOS, follow these steps: How to reinstall macOS
The Apple Support YouTube video below can also help.
How to reinstall macOS from macOS Recovery — Apple Support - YouTube
To find more answers to questions about macOS, visit the macOS Support website.