All you need to do is, save this as sendInsta.sh:

#!/bin/bash

SCREEN_HOST=192.168.178.50

if [ -f site.png ];
then
    rm site.png
fi
pageres instagram.com/$1 320x480 --format=png --filename=site \
    && convert site.png -crop 320x480+0+230 +repage site.rgb \
    && curl -i -X POST -F "data=@site.rgb" "http://$SCREEN_HOST/api/fullscreen?x=0&y=0&w=320&h=480"

And modify SCREEN_HOST to the IP shown on your display, after you have followed my previous posts:

Then, run

./showInsta.sh pauls_3d_things

Details

You will need pageres, imagemagick, and curl.