You cannot upload video direct to tripoto first you need to upload them to Youtube or in Instagram. Then only you can simply click on the plus icon. click it and you will have various options to add photos, video from Instagram or YouTube or even Facebook.
Hello! You need to upload your video on either Youtube or Vimeo first. Then you can embed those videos in your post. Follow this link to share travel stories and videos: https://www.tripoto.com/trips/create