Book: Meathead: The Science of Barbecue used to be the goto
Transfer any dish you know well inside that requires an oven as a starter. With the oven mentioned, there's no shame in doing a chicken in the oven and finishing it off in the BBQ and this works in reverse wrap what you've cooked in foil and hold it in the oven don't just crowd the grill esp don't mix raw and cooked.
Food safety is the biggest contender you'll have, cooking outside will create so many more variables and the nature of BBQ esp when starting out can really mess things up if you just assume, even upper end stuff like Green eggs and Blackstone need adjustments on a windy day. Get decent thermometers (not one) and run through some good food safety tutorials.
With that in mind, have a raw to cooked flow with separate tools I go left to right using colour coded tools red = raw, yellow =cooked do what works.
Low and slow is the way to go
Remember it's the rendering of the fat hitting the heat source that does the BBQ flavours this is (fun as a veggie), so if you're doing steaks and such start heavy and work down to lean.
Fire triangle: Air Fuel heat: once your going Air becomes the dominating force, don't forget your airflow.
Find a good source for meat if your local butcher is good, becoming a regular is basically BBQ school with deals.
Keep doing it, prob we have here in the UK is there's a mentality only to do BBQ when it's a special occasion and the weather is perfectly sunny. Just fire that thing up for any reason, I don't get why we wait until 20 relatives are round Uncle Jim's already pissed halfway down the kids slide, and the FIL is starting you down to try and one shot it :D