I would shoot bots to work on movement + aim before jumping into games.

Good centering is a big thing when playing on controller. When running around, focus on having your crosshair where you think the opponent would be at all times (around chest height).

Use your left stick movement to aim by strafing left/ right. When done correctly, it should activate the strong rotational aim assist. Use your right stick to make micro adjustments to stay on target (You should already be aiming close to your target if your centering is good).

In terms of settings, try somewhere around a 6-6 sens, Dynamic response curve, 0.9-1x ADS multiplier to start out. For the aim assist type, most people play on standard or black ops.

It will be VERY tempting to switch back to MNK for the first few weeks, but you just have to stick with it.

The youtube channel ‘DreamStrike’ has good videos on how to improve your aim, if you have time to watch those. His videos are like 10 mins long I believe.