You can easily share files between BlueStacks and Windows using shared folders. Just place your file inside it and you can access it from both Windows and BlueStacks.
Let's understand it:
The default shared folder in Windows is located in C:\ ProgramData\ BlueStacks\ UserData\ SharedFolder (assuming C:\ is your Windows installation drive). In BlueStacks, the same folder is located in (Root)/ sdcard/ bstfolder/ BstSharedFolder.
BstsharedFolder is bluestacks shared folder with your pc contents and vice versa.
You have to put files into the above folder to make accessible from pc as well as from bluestacks itself.
Additionally, the default Windows Library folders are accessible from BlueStacks. They are located in /sdcard/bstfolder/ as Pictures, Documents, etc.
A file manager app is required to navigate folders inside BlueStacks. In this answer, i'm using OI File Manager. To share a file, follow the steps below:
1.Download and install OI File Manager in BlueStacks.
2.On Windows, navigate to BlueStacks Shared Folder [C:\ ProgramData\ BlueStacks\ UserData\ SharedFolder] and place the files you want to use in BlueStacks (like photos, videos, downloaded APK files, etc.). You can also use the Windows Library Folders for this purpose.
3.In BlueStacks, launch OI File Manager and navigate to BlueStacks shared folder [(Root)/ sdcard/ bstfolder/ BstSharedFolder]. If you have placed files in your Windows Library, locate the respective folder from bstfolder directory in BlueStacks.
Similarly if you want to access BlueStacks files from your computer, copy the particular file to BstSharedFolder using OI File Manager and the same file will be available in Windows SharedFolder location.
Note: This article is originally written by David. Source