Is there any way around using so many if statements and while loops to run a programme? there has to be, right?

import sys
shopping_list = []

command = input("""Would you like to start your supreme AI shopping experience?\n Y/n""")
def show_help():
    print('\nSeperate each item with a comma.')
    print('\nType DONE to quit, SHOW to see the current list, and HELP to get this message')
    add_item()
def show_list():
    count = 1
    for item in shopping_list:
        print('{}: {}'.format(count, item))
        count+=1
    add_item()

def add_item():
    command = input('\nPlease enter the name of the item:\n')
    if command != "DONE".lower() and command != "SHOW".lower() and command != "HELP".lower():

        index = input("Add this to certain spot on the list?, "
                "\ncurrently we are on number {}\nPRESS ENTER for last spot and continue or give me a NUMBER. NO LETTERS or "  "SYMBOLS:\n".format(len(shopping_list)))

        if index:

                shopping_list.insert((int(index)-1), command.strip())

        else:
            shopping_list.append(command.strip())
        add_item()
    else:
        function_dict[command]()

def exit():
    print("""Thank for shopping with us.
I know it's a bit late but we dont really sell anything...\nThe shopping list looks neat though!\nOk bye now""")
    sys.exit()    

function_dict = {"Y".lower():add_item, "HELP".lower():show_help, "SHOW".lower():show_list, "DONE".lower():exit}
function_dict[command]()