I am a new modder basically trying to learn from scratch this summer, and I don't understand why when I load up the mod it can't find the model for the item adamantine_ingot (leaving a link to my GitHub below) and moved on to making other items without texturing them. Also, need one of my items to open a GUI from a hand and I don't understand what is all necessary to make one open. Like is it necessary for every type of GUI to have a newly registered handler(if so what is necessary for new handlers) or how many things need to be fulfilled? Also, what is the difference between playerin.displayGui() and NetworkHookup.OpenGui()? If you look through the rest of my code I know that I haven't been doing things for both server and client sides but was more concerned in getting the basic idea to work in the first place.
Link to the model of adamantine_ingot: https://github.com/SRGTOblivious/BlocksAndBeholders/tree/master/src/main/resources/assest.blocksandbeholders
link to the main page of Github: https://github.com/SRGTOblivious/BlocksAndBeholders