Hi new, whats the attitude rating by characters and its effect. Is it on the lines of charisma,people liking you ?

Yes. Vendors will give you a little better prices if they like you, and raise their prices if they do not. If an NPC's opinion of you gets too low they may refuse to talk to you (you may be able to bribe them to increase their opinion), and eventually they will become hostile and attack you (or call the guards, depending on the situation).

Thank you !