Can anyone help me with this please? I have to take backup of my Windows

Can anyone help me with this please? I have to take backup of my Windows.

Instructions are available in the very dialog you show. The file system is inconsistent. Thus, connect it to MS Windows, then have it checked using the Windows drive checking tools (you can, if you wish, use the Windows command line tool chkdsk like the message says). Then close Windows completely after having disabled "faststart" in Windows. That ensures that Windows will fully close the file system when shutting down. Only when an ntfs file system is healthy and clean will Ubuntu seamlessly access it.