There are multiple ways to send a video file through email: attachment, cloud storage, file hosting, etc.
The easiest way is through email, but if the file is bigger than 25 MB, the email services will reject.
I would like to recommend uploading the video to the following services then you can simply paste the link with the video in the email you're about to send.
Cloud storage:
All these are free. Create an account, upload the file and then share it with your contacts through email.