On a computer to iCloud.com and log in with your Apple ID
Then go to ‘photos’ and your videos should be there allowing you to browse and download them
If there is nothing then you need to switch on iCloud backup, and if it is too full to have uploaded all of them then you can upgrade for as long as you need, or copy what is there, delete from your phone, wait for the next batch to upload etc
Alternatively you can use another host such as Microsoft, Dropbox etc
You can set these to automatically synchronize photos and videos or select and transfer the specific ones you need
To send specific videos:
On your iPhone browse the videos,
Either open an individual video and click the ‘square box with a vertical arrow’ icon
Or choose ‘select’, tick a few videos and then click that box/arrow icon
Assuming you have set up Microsoft OneDrive, Dropbox etc, then you can select these from the icons shown or actions list
Once you have the videos hosted you could share links or download to a computer
With some DVD players you can just copy the videos onto a writeable DVD and they will play, but it is neater and will work with more players if you ‘author’ a ‘proper’ DVD with DVD software - which can be free