If i go to a different town or city and do some quests there will they be too hard or impossible for me to do because I'm not a high enough level / don't have good enough gear? I'm just wondering as iv got to a hard part in the story and i want to get better gear or weapons before i try do it again and idk where to do quests after whiterun.

Also do dragon attacks happen randomly as i was on my way to the quest place mentioned above and a dragon came down and attacked me, i killed it then went down the road there were say 20 hostile enemies at this place and another dragon comes , attacks me and the enemies, but all the enemies attacked me while the dragon attacked my enemies and me so i died.

also where do i buy better weapons/armor, iv been to the blacksmith to the right when you go in whiterun but all his stuff is worse than the gear i already have, is better gear for sale at better places? or do better items become available from them all when you level?

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