It's quite hard to use the public transportation system in Budapest if you compare it to cities in other countries.
There are almost no signs in English, and it's impossible to hear the station names that they are calling out (unless you can pronounce Hungarian). Some cable cars have electronic displays that shows the station name.
The public transportation is also very noisy and warm (in the summer).
Everything is however not bad. The Budapest card gives you free access to public transportation, and Google maps can say where to board a certain train/bus, and how many stops to stay on it. Prepare to get off the train/bus before your stop. They usually open the door before they have done a full stop, and they only stay about 10 seconds at each stop.