A.G.
Yelling at a toddler is like yelling at a rock or some inanimate object. It won't matter what you say or how loud you say it, it will still sit there and stare at you and not register a thing you say to him.
Right now you need to first be his mom. Forget the "friend" bit bc if you don't both your negative behaviors will start spilling over to when you are out in public or worse, when he starts school.
You are the mom. He isn't the boss and he needs to know it. You are in charge of his safety. If you can't teach him (kindly) to listen to you, what will happen if there is an emergency? Let him know you mean business. If you tell him not to do something and he does it anyway, let him know there will be consequences. The next time he doesn't listen, give him the consequence (at that age, time out only works for a minute or two).
Stick to a routine so he will know there are certain behaviors he needs to have every day. You are going to have to explain everything to him and show him how to do things every single day, almost every moment of the day. Once you can see he can start doing things on his own, then let him.
Try keeping his diet healthy and natural. No more processed foods. Only fruits, vegatables and whole grains. Water down his juice, no sodas, plain white milk - no flavored milk - etc.
Keep him busy. Keep him with you. Give him little jobs to do and let him help you while you do things. When he wakes up, have him hand you the diaper or have him hold the wipes for you. Let him walk with you to throw the dirty diaper in the trash. When its time to eat bfast, have him "set the table" by putting his napkin on the table and then gradually add in his spoon, cup, etc as he gets the hang of it. After he eats, have him help you clean up - give him a towel to clean off the chairs while you wipe down the table. When its time to put away toys, have him help you put them away, even if it means putting them in a basket. When you sweep, have him clean a corner w/the dustpan and brush. When you do laundry, give him a few wash cloths to fold while you are in there. When you make the bed, have him help you pull the covers off. I'm sure you get the picture.
The sooner you get him into a routine and he starts listening, the sooner you can spend time with him w/o having to worry about tantrums and yelling and then you can actually start to build that friendship with him that you want.