Spend a several hours on YouTube. There are full, in depth walkthroughs of the entire Mavic Air, as well as every single menu/app option. It's a lot to take in, but very intuitive. There are also lots of videos on the most common mistakes new drone pilots make, so make sure you watch those too. Learn, learn, learn - that is what will prevent you from destroying your drone with a rookie mistake.
If you can, get your hands on a cheap drone from Amazon or similar so crashes don't matter and you can build muscle memory for the controls until it becomes second nature.
Learn about proper battery usage and storage - this is one area in particular that is easy to neglect but is extremely important. Actually read all the manuals that come with it.
Start in "beginner" mode to get comfortable with the drone - it limits speed and distance for you. Don't use any features or rely on any features until you have researched or read about them first and fully understand them.
Don't fly in strong winds, and remember wind generally gets a lot worse the higher you go up - wind speed at the ground is not the same as wind speed 100' in the air. Especially for your first flights, really try to find a calm day so you don't have to worry about wind.
Oh, and don't fire it up in the house
After you have spent a lot of time learning about the drone, take it out to a big open field or something for the first flight. Don't fly until you have at least 11-12 satellites (inadequate GPS is how many people lose or crash their drones). I assume you got the fly more package, so burn through all 3 batteries just practicing basic motions and maneuvers and getting comfortable with things. Do not run the batteries to zero, it is good practice to stop at 20-30%.
After you are comfortable with flight, start learning how video works, with frame rates, shutter speeds, etc (unless you already have a background there of course). You will want to be shooting in full manual to get the most out of the drone.
