I'd like to know how to get tasks from npcs. As i understand, you should normally select them and type /task but i tried it on every guard, sentinel and taskmaster i could see and it doesn't seem to work that way. Also, i'd like to know how quests works and how many of them are implemented (i heard there is a bug with some client version).

Thanks for your time

I'm afraid that tasks are not implemented yet. If they were you would have to find the correct guard for your level range...but for me not a single task yet, too.

For quests you need to find NPCs which are marked by a yellow circle underneath their feet. After right clicking them, they will ask you if you want to accept their quest. Since the last update there shouldn't be any problems at all, no matter what version you are using, to take quests. (However, I have noticed some problems with missing horse routes, missing quest mobs, and wrong quest rewards...) AfaIk, you'll find most quests in Albion - but it's still far from the number of quests you'll find on Live. (There are the Beginner's quests (~ level 1-5) which you will get near your starting location, the Epic quest for level 50 players, and some others for various levels all over the world.)