Meeting boyfriend’s Austrian parents first time

Hello - I am a Canadian woman (late 20’s) meeting my Austrian boyfriend’s (he is the same age) parents for the first time next month. We will be meeting up at a cafe for a meal together in Salzburg. What are the cultural expectations in this situation? I normally would bring a small gift (nice flowers, bottle of alcohol, etc.) if we were coming to their home, but since we will be meeting with them at a restaurant (only), I’m not sure if I should bring something or not. If so, what would be appropriate to bring? I also am not sure if I should pay for the meal (for all of us) or if it would be seen as an odd thing to do. I would like to make a good first impression!

Thank you