To open this, you would typically right-click on the file in the sequence (the .001 file) using a program like 7-Zip or WinRAR and select "Extract." The software will automatically bridge all numbered parts to recreate the original MP4 video.
: This indicates it is the 11th segment of a split archive. To extract the contents, you must have all previous parts (001 through 010) and any subsequent parts in the same folder.
Do you have the of this file, or are you having trouble getting the extraction to start?