>>722932AFAIK:
1: WebUI stands for Web User Interface. Automatic1111 is the version for the UI. NovelAI is a very known model.
2: Not that I know. You can merge models to make a new one based on other 3, but you can keep merging and experiment. Berry Mix is a known merged model that's pretty good and used by a lot of folks
3: So, i'm not an AI expert, just a guy that decided to install the shit from Voldy. But, (afaik), AI training is making models, embeddings, hypernetworks that give differente results based on the dataset (the pictures you feed the AI). I never trained a model, because it requires a REALLY good setup. Plus it seems complicated.
IDK THOUGH