Assigning a REST request to a app variable

Hi guys! I’m searching a way to use the data I have in a database but because of how the API works I cannot simply ask for the item that I want. It requires me to use double quotes and AppGyver just changes my double quotes to %22 (First question would be how to solve it). But trying to solve that, and to to ask and compare for the whole database every time I want to use it, I want it to be assigned to an app variable on every initialization, or even better, creating a local storage and checking the date of last update from the server, if it doesn’t match, than it updates the local storage. People are doing stuff like that easily on videos in youtube, but when I bring the examples to my case it does not work correctly =( .

TLDR: Want to have a list of objects that I can use to compare with an user request to create another list with only those items but can’t just make a get request with the item I want.