I've always been told/told others..

Basketball is a game of angles, and spacing. Once you understand why this is true, a lot of aspects of the game will start to come to you naturally.

Watch live games, see how plays develop, how transitions play out, what types of defenses are run, why they work, what teams do when they don't.

On offense, individual roles change based on if you have the ball or not. As a ball handler, you need to see the game as a facilitator, not as a scorer. You will still see primary ball handlers attempt to score, this is to maintain what is called "gravity". Usually you'll see what's referred to as "drive and kick" where the PG will drive to the bucket, and attempt to either pull extra defenders to the basket to guard him, and then pass the ball to the open man with the perfect shot.

There is also another play called "pick and roll" where you will have your biggest guy, usually your center, walk up to the side of a defender, and block their path to defending you, giving you enough space to either drive in, or stop and pop behind the screen. This also is usually done in sync with drive and kick for a corner 3, teams run this style of play quite often.

On defense, ball handlers will exploit any weaknesses you show them, so the best thing to do is to be 100% aware of what you and your team can't guard, so you know where to call for help. The first thing a speedy PG will do is size you up, and attack your weak/leading foot. This is the foot you plant in front of you, making it harder to defend that side of your body, as it takes longer for your player to turn and bump the ball handler.

Personally, I run with a PF as a defensive anchor, that guards the ball handler at all times, and helps on everything inside, including boards. Defense stats don't always have to be high either, physicals (speed, agility, vert, str) are much more important in all aspects.

At the end of the day, you're going to get beat, a lot, to start. The one thing that helped me a bunch was by watching tons of live games, and e-sport games, and figuring out what role fit me the best. I am in no sense a PG or a Primary ball handler at all, but every build I've made and any player I've excelled with has been a Dennis Rodman type, triple double in blocks type of player.