Yes, you can. The easiest way to do so is by copying the video from the SD card onto a computer and uploading it from there.
I think you get a camra and record
The DSi can't make videos.
You can download the Youtube application from the eShop if you want to watch Youtube videos, you can not watch video files such as mp4s, but if you upload them to Youtube you will be able to watch them :)
You can't :(
You will need to go to the Nintendo eShop and download the YouTube app with no cost. Then, when it finishes downloading, you will be able to search for any YouTube video.
Yes, but if you want to watch YouTube videos, you will need to download the YouTube app from the Nintendo eShop first (at no cost).
Yes, the 3DS can be used to watch YouTube videos. However, the YouTube app needs to be downloaded first from the Nintendo eShop (at no cost).
No. The 3DS does not have the processing power to access YouTube, Vevo, Fuse.tv, or any other websites that have music videos, let alone even play a video at all. It's just not what the 3DS is meant for.
No, you can't upload your photos from your 3DS, but you'll have to, instead, do the process via your SD card.
yes
YES
unfortunately, no
There is always a client for your favorite app or service for different platforms or devices. The main thing is to try to find information on the Internet for the query you are interested in. If you want to always have access to your channel and promote it, then there is a special service lowcostsmm, where you can get views, likes or subscribers for YouTube from live people or bots.
search on youtube