Questions for my game

Hi there, sorry if all of this has been asked elsewhere separately but I couldn’t really find what I was looking for. I have a few questions so whoever wants to answer what feel free and hopefully this will help other people as well.

  1. Looking to make an animation where the character throws something and when it hits the ground it then summons another entity. How would I go about this in a simple way?

  2. In my game you’re limited to a certain amount of summons and you pick them before you head out. Would it be realistic to have the selected ones be pre-rendered somewhere in the background to avoid lag when using them, since its a low amount, about 30(including duplicates)?

  3. How would I go about making a UI to select whats available to summon, and cycle through it randomly from the others? Like only have 5 things available to use in your “hand” but if you dont like what you have you can shuffle it back into the “deck” until you get what you want.