you can only get it from a squid... sorry... you cannot make a squid ink...
They can expel a blackish substance which looks like black ink.
It's for their own protection - a way of repelling predators it blocks enemy sight so the squids can run
NO!
You can refill you ink cardridge by taking it to various stores that refill cartridges. Wal-Greens offers to refill ink cartridges for a reasonably low price.