He sounds great! Soon he may want to learn to tie his shoes. Do not push this.. It is a fine motor skill and can take till they are in kinder to figure out.
Give him multiple instructions and see if he can complete them without reminders.
"I am getting ready to go to the store, I need your help. Honey will you please go and get the grocery bags and put them next to my purse? I also need you to put my cell phone in my purse. It is on my dresser. Remember we do not buy snacks and drinks at the store. Go to the kitchen and pick out a snack and a juice box for yourself and please bring me a water bottle. Thank you.." Always congratulate him on helping you and remembering these things. In the beginning this may be a lot, so you can build up to it.
I used to call out the list of groceries we would be shopping for. Then at the store I would ask our daughter to remind me, What do we need here in the fruit area. On the pasta aisle.. what did we need on this aisle? At 4.5 he can sit down and "write" a list along with you. He can draw pictures of the items or write the letters he knows for certain items. Let him write out all of the dairy items or the bakery items.. Of course do this the day before not right before you are getting ready to go to the store.
Let him carry his own list and ask him to "remind you what is on his list".
Have him sort the clothes in 3 laundry baskets. Have him help you take the dry clothes out of the dryer.
He can button all of the shirts that are hangers and zip all of the zippers (fine motor therapy). Eventually this can be one of his chores.