I'm wondering about that little appendage that’s coming out, what’s that and what’s it doing? Seems to be going away from the light.
I tried to google but most result for my searches were just offers to buy a new cactus
Looks like it is showing some etoiliation on the new bud. It has to bud to continue to grow as it was cut of when planted. Aerial root may mean that it is root bound in that pot.
Larger pot with the correct soil for dragon fruit, more sun.
I have no idea, bought it because the fruit / flower looked interesting. It’s probably a dragon fruit, judging from the other comments, the fruit looked similar. It came in this pot and I water when I notice that the earth is dry
It's a dragonfruit. For reference, it's not like a standard cactus. Treat it more like a tropical plant. During the warmer months, they like to be watered frequently. In the winter, you might need to water it once or twice a month.