Q.calla lilies
I started them from seed and they are about 2 to 2 1/2 inches tall. Do I pot them in a small pot and then plant in the garden. I just don’t want the sun to kill them if they are too tender. I have them on the sunporch which has a roof and they get a little sun.

I would move the strongest seedlings to a bit larger pot and allow them a bit more time.
You should slowly harden off the seedlings to the outdoors.
https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/calla-lily-seed-info.htm