its a frustrating mission for some .. the thing to remember ..is tap your Keys do not hold em down and yes you must complete the mission to play the following story missions
keep trying you'll get it through it . and yes you have to complete that one to finish chapter 2 of the game
what helped me the first time i played it was to plug a controller into my PC .. i have an old logitech dual action game pad .. worked perfect . but now i just use a KB + mouse ..but either way gently tap your keys to steer and i inverted the keys so W is up S = down you can change that right in the games settings under invert flying controls ..so keep tapping W every now and then if you need to gain altitude and press S to steer down to make it thru the hole at the end of the canyon run ..you will meet willis at his plane at the end of the mission ..and after speaking to him you will see that you have completed chapter 2 of the game .
Spoiler: Show
also try watching a few video's online of other people playing that mission .. (look on you tube ) so you get used to seeing what you need to do to get thru it
https://www.youtube.com/watch?v=4kEdpOD8cvM
frag maniac does a nice job with his vidz
IGN has a guide as well located here
https://www.ign.com/wikis/far-cry-4/Campaign_Missions
good luckand happy flying .. i think you CAN DO IT
oh and i know how ya feel i hated that mission at first .. till i got the hang of it .. now i really like playing that one ..yes i have played through far cry 4 dozens and dozens of times .. it's still my favorite game to play after over 5 years of playing it.
Well you had to do that mision before , as it's a required mission to progress in the game to get to the key to the North Mission , there is no other way the game has ever worked without having to do all the story missions, to get to the mission where you get over Kings Bridge and open the north . i have owned the game since the day it shipped back in 2014 , and the missions for console version are exactly the same as for PC .
all i can say is good luck and keep trying .. you'll get there .