When I first moved to Italy, I didn’t speak the language one bit. I was able to say Hello and Goodbye, if that counts
I haven’t used any apps or book, I simply began learning by talking to people at work. Few of my colleagues spoke both English and Italian so I was able to learn, bit by bit. I think this is the best way to learn a language, by exercising with locals, it really helps both the vocabulary and pronunciation!
Italians also translate every single movie and foreign show on TV, so if you watch it often enough, you’ll keep hearing Italian over and over again… it’s impossible not to learn anything by hearing the same words every day.
As far as time frames go, I’d say I was able to understand most of a conversation and was able to reply (with simple and badly pronounced words… ) within 3 - 4 months.