The key to not staring at your bar too much is to get your skills into a configuration that is comfortable to you and then just use it. With enough time you'll just know where everything is and will only need to look at bars to check on cooldowns(keeping all of them physically near each other on the screen helps minimize time spent staring, too). Regarding button presses themselves, a great strength of the keyboard is naturally the sheer number of buttons you have on hand. Creative keybinding(a common example is binding letters near the WASD movement keys to abilities) can ensure that all of your skills are close at hand with plenty of room to still have the Quality of Life shortcuts around.

For targeting, I use a combination of tabs and directly clicking on enemies/targets. I can't say for sure whether or not it's the most efficient way of going about it, but it works for me.