I've used WoW-Pro for years and in WoD, Legion and now BfA it's been awesome for just going on auto-pilot and working your way through a zone. It has 3 levels of depth you can set, so you can set it to just do 1) the main story, main points of interest and rare mobs and treasure that aren't far off the beaten path; 2) every quest with a more thorough dive into the side stuff; 3) absolutely everything.
When you have completed your third zone, you should be nearly max level, but you still have work to do! Head back to your faction hub and complete the last foothold quest to unlock your fourth mission table champion. After, you will want to do your newly available invasion missions for your faction. This quest chain is one that will be time gated by reputation levels earned with the 7th Legion for the Alliance and iThe Honorbound for the Horde. Complete as many quests as you can and then finish up your leveling with side quests you may have left in previous zones as necessary.
The World of Warcraft API has a list of functions that you can interact with and to talk with WoW using Lua. These are your building blocks for manipulating WoW windows and chat boxes and so forth. Looking at these for the first time can be very daunting. But don't be discouraged. After getting more familiar with Lua the WoW API gets much easier, and the documentation gets much easier to read. Keep in mind there are many different ways to accomplish your goals, so when going though the API keep looking until you find a way that best suits what you need.