If a picture taken with canon rebel t6 is sent to my Android phone, will it look the same printed from my phone vs the sd card from camera. Want to have a picture printed to canvas, originally taken on camera and then sent to my phone.
It depends on how the picture is being sent to your phone.
Assuming you took the picture in .JPG, the printed image will be the same as long as the method used to send the picture doesn't compress it. A more compressed .jpg will have lower quality than the original.
For example, if you insert your SD in your computer and upload the picture to Google Drive, then download it to your phone... the picture will be the same. If you send it to your phone via WhatsApp, it'll compress the picture.
If you are using the Canon Camera Connect app, as far as I know, you can choose whether to resize the picture or not when transferring the image.
I use the Canon Camera Connect application in Android, and it has the same resolution as using the SD card. What I see as an advantage is that you could send RAW types too. So indeed if you like to use the Lightroom Android version it could be useful.