I've always let my children help me with everything from the time they could walk. They would help me cook/bake by measuring things, adding things in, stirring, mixing, etc. My 12 yo son is now able to prepare an entire dinner by himself, and my 9 yo daughter is almost there. (I won't let her use the stove without being there to watch her.)
They helped with everything in the household - laundry, cleaning, shopping, etc. And they had their own chores to do from the time they were 2.
I have always had them make their own purchases, if they wanted to buy something with their money. They have no trouble approaching an adult and asking questions or placing orders. They've been able to order their own dinners at restaurants since they could talk.
All of these things instill confidence and help them to be more self-sufficient.
I remember - vividly - how my dad made me go into a McDonald's when I was 8 yo and order our take-out for our family (there were 7 of us!). I was so nervous, but he wouldn't go with me. So I did it. And let me tell you - I was SO proud of myself when I came out to the car with that order! : ) That was one of the best things he ever did for me.
Lastly, if you haven't yet given your children chores, and you want to, my advice is to do it this way..........
First step, tell them what it is you want them to start doing (eg., sweep the floor).
Second step, demonstrate it two or three times. (not all at the same time - I mean a few times over the course of a few days)
Third step, help them to do it a few times.
Fourth step, let them do it by themselves, while you supervise.
Last, turn them loose and let them do it on their own. They won't be perfect at it, of course. Let them continue to do it, and they will improve. Never, EVER re-do what they have done. That will destroy self-confidence and make them less self-sufficient. If you really can't tolerate how they do their chores, go back to step three and start again.
Blessings.