I just started to play Battle for Wesnoth. I did some of the tutorial and I have started a novice campaign. When controlling say the elven archers, I wish to do an attack by bow. Given that it is a range weapon, I would assume I could be several squares away and attack the enemy. Every time I attack with it though, it seems that the game requires that I be adjacent to the enemy to carry out the attack. This is by clicking on the archer then clicking on the enemy. Is there a way to do a true range attack with a bow from several squares away? Seems like the learning curve would accelerate quite a bit if I find out how.
No, this is not possible. Units can have a melee attack and/or a ranged attack in Wesnoth. When you attack a unit, you must be adjacent to them, but they can only respond with the type of attack you used. So if you attack a unit with no ranged attack with a ranged attack, you are guaranteed to be safe.
Try to use your ranged attacks first and finish off the enemies that they attacked. This will allow you to move other units into that space to help shield your ranged units from being attacked back on the following turn.