First time Axolotl owner

Okay, so in a few days I'm bringing home my first axolotl. No matter how much research I've done on them I still feel like I'm missing something! So, tell me if I'm missing something: The axolotl I am getting (off kijiji) is an albino GFP axie, who is 6 inches long. The current setup the seller has it in is a 20g tank, no sand just rocks, unsure what type of filter etc and he is feeding it earthworms. I've been originally planning to feed my axie pellets, brine-shrimp, blood worms and earthworms. I'm not sure if I am going to hand feed or cup feed? Can I do both? I was going to add in sand to the tank as I've heard its better for their toes, should I wait to do this or do it right away? Also as I do not have a basement, would the tank be ok just in my room? I live in Canada so I'm worried about the temperature changes. My house is usually 20 degrees Celsius. I'm going to remove all the rocks/pebbles he has them with as they seem slightly small, when should I do this? If I fully change the tank setup right away will it stress my axolotl or is it better to get it over with? Also if I wanted to get a second axolotl to go with this guy in the future, would I have to find one the same size? Thanks

If you're going to do drastic tank changes, like switching from rocks to sand, you should do that before you get the axolotl. Gravel is a big no. A fine play sand is good, and bare-bottom is also good.

You can feed an axolotl however you want as long as you get them to eat for the most part, if something wiggles or falls in front of their face, they'll snatch it. I have a fairly deep 40-gallon tank, so I didn't even try hand feeding until fairly recently, but my almost-year-old axolotl was pretty cool with it even though he wasn't used to it. Like I said, they'll snap at things that move (including each other sometimes). Whether I drop a worm or pellet on their face or hold a worm in front of them with my hand (while soaking my arm up past my elbow. lol), they'll snatch it.

I live in Missouri, so I'm not sure, but I generally assume most parts of Canada are usually fairly cold? Your house will never be too cold for an axolotl no matter where you live. Without a basement, it IS easily possible for it to get too warm, perhaps even in Canada (like I said, I don't know Canada very well. I just assume it's cold since it's north of our coldest states. lol). Little fluctuations are ok, if it's gradual and just a few degrees. The water shouldn't get warmer than mid-60's Fahrenheit though, so screen lids are good for allowing evaporation and you can always have a fan blowing on the surface of the water to keep it cool if necessary.