If you are new to chess and the DGT Pi is your only chess companion, then I would suggest you learn the basics of the game by concentrating on "Open" "Closed" and "Semi Open" Books and become familiar with what is meant by those opening book categories. "Open" type games are usually King pawn 1.e4 games, "Closed" are generally Queen pawn openings for white 1 d4, and "Semi open" are Sicilian style, among others. The French is in there somewhere. Add the Indian repertoire after spending time with the first three types. After that you have 95% of chess covered. You may discover what type of player you are by which of those opening books you like the most. As a novice, avoid the flank book, the varied is too broad and the rest are too specialized.
DGT Pi Chess Books
BTW You have chosen a very difficult chess coach in the DGT Pi. I hope you enjoy it and get years of use out of it but I have never heard of a novice or beginner using a DGT Pi to learn chess. Perhaps you were given it as a gift. You will not be given reasons for the computer's selections. It does not display variations and alternative good moves. Also, selecting Stockfish as your opponent is a thankless feat. Even at Zero setting I don't think Stockfish is designed to throw in random legal moves. I believe it simply stops evaluating board positions after looking 1 or 2 moves ahead. You would have to come up with a plan that succeeds in 3 or 4 moves. I suggest selecting an engine which goes down to ELO 800 or 1000 and try to beat the machine 25% of the time. Someone with more experience with engines and the DGT Pi can shed better light on the topic, but I don't think there are a lot of Pi owners out there.
As a beginner I would recommend using the the Rodent III engine and start playing against personality Zero, if you can beat zero regularly try Helpless, after that Lea, then Blias, then Rita, then Novice.
I'm very much a beginner and just got a DGT Pi to practice/play with. I started learning last year and have only played on a few misc apps doing puzzles and games. I'm actually finding the change to a real board really changes everything and I'm missing a lot just because of the change in physical appearance. I'm playing using the Stockfish engine on level 0 right now and finding it challenging.
My question is about the books. As a new player finding level 0 challenging should I just turn off the books or pick a specific one? There are 15 books available and by default it's set to use "varied". Some of the books I can kind of guess at how they might impact the game by the name, others no idea. For example what do the "Fun" or "Pro" books do.
Thanks