Confusing question about attack move and attack move click
HI, I am new to the game. I have been playing adc for a while, but I think I lack the skill to dodge enemy champions' abilities and I don't do well in group fights. I have been watching videos introducing attack move. Using the default settings, attack move is botton A and left click, attacking the nearest enemy I encounter. But I found out that shift and right click is also like attack move. I wonder if there is any difference between these two controls? Also, about attack move, I learned from the video that by using it, I attack the nearest enemy from where I click, which is very confusing because it doesn't seem to work for me. For scenarios, if I am Adc, say Ashe, facing a tanky melee champion with relatively high attack damage, say Garen. how do I fight using attack move? If I press A and click on Garen, do I need to right click him or attack move click him again if he moves out of my range and enters my range again, or will I auto attack him whenever he enters my range?
