In addition to the steps below, you may want to also remove the .gitignore file.
Some frameworks may automatically produce the .gitignore file so you may want to leave it.
Linux, Mac, or Unix based operating systems
Open a terminal and navigate to the directory of your project, i.e. - cd path_to_your_project.
Run this command:
rm -rf .git*
This will remove the Git tracking and metadata from your project. If you want to keep the metadata (such as .gitignore and .gitkeep), you can delete only the tracking by running rm -rf .git.
Windows
Using the command prompt
The rmdir or rd command will not delete/remove any hidden files or folders within the directory you specify, so you should use the del command to be sure that all files are removed from the .git folder.
- Open the command prompt - 
- Either click - Startthen- Runor hit the key and r at the same time. key and r at the same time.
 
- Type - cmdand hit enter
 
 
- Navigate to the project directory, i.e. - - cd path_to_your_project
 
- Run these commands - 
- del /F /S /Q /A .git
 
- rmdir .git
 
 
The first command removes all files and folder within the .git folder. The second removes the .git folder itself.
No command prompt
- Open the file explorer and navigate to your project 
- Show hidden files and folders - refer to this article for a visual guide - 
- In the view menu on the toolbar, select - Options
 
- In the - Advanced Settingssection, find- Hidden files and Foldersunder the- Files and Folderslist and select- Show hidden files and folders
 
 
- Close the options menu and you should see all hidden folders and files including the - .gitfolder.
 - 
- Delete the - .gitfolder
  Delete the- .gitignorefile ** (see note at the top of this answer)