It would be interesting to know what specific tasks are assigned to Flick, but this is classified information (at least for now). Barcelona cannot publicly admit that they have no goal of winning La Liga (due to their status) so now we can only guess what they want from him. If we draw an analogy with Xavi, last season they expected any two trophies from him (even the smallest one like the Spanish Cup). It seems to me that the target level for him is set as “no lower than second place in La Liga and no less than the quarterfinals in the Champions League + some title.”
I don't know if Hansi Flick will lead Barcelona towards their goals, but he will have to admit it is a difficult task. Real Madrid, the strongest of its rivals, added Mbappe to its squad and is now very strong. Barcelona must show its best performance against Real Madrid and other teams. The road to the championship will be a very difficult road. I think the minimum target should be to finish the league in second place.
At the moment, bookmakers quote Real's chances of winning the title as 1.49 and Barcelona's as 4.50, quite eloquent figures to understand the difficulty of the task. But as I said, I don’t think that the Barcelona management is so crazy as to demand the title as an unambiguous condition, they will not admit it publicly, but the real requirements will be approximately the same as what we expect (not lower than second place, some kind of cup, etc.) .