Would like to change our points from Dream to cash points

I believe you are talking about AirMiles points/miles.
You cannot change existing miles from Dream to Cash
You can go into your preferences and state whether you want newly earned points to go to Cash.

This is socks because the threshold for redeeming Dream miles is absurdly high, so you get stuck with 100's or 1000's of Dream miles you can't redeem. A quick look seems to show the cheapest and least desirable merchandise item costs about 800 Dream miles.
From the AirMiles FAQ
AIR MILES Reward Miles cannot be transferred between your Cash and Dream Accounts. However, you can change your preference as many times as you like. You can set up or change the balance ratio for your Miles by moving the preference slider from 0% to 100%, towards either your Cash or Dream Accounts. Once set, future Miles will be added to your accounts the way you want. If you change your mind, simply sign back into airmiles.ca and change the preference slider to a different ratio. For more information, or to update your preference, click on the Get Miles tab and select Set your preference; or just click here.

https://www.coles.com.au/about-coles/flybuys

Using the 'P' key, 'C' key turn the key to the PROG position, PRESS the 0 (zero) key and then 0 (zero). At this point, press the key of the item that you wish to change or Enter the PLU # and press the PLU Key. If the description of the item is ok then press 'cash/enter' and then press it again. You should be on the PRICE/Halo line, Change the amount to the correct amount and press cash/enter at this point you can then press the clear key and then turn the key to the 'REG' Position. Press the Key of the item you changed and it should display the new price.

You can't normally turn off the clerk system as it would facilitate terrible fraud. You are just supposed to sign on and start using it.
All cash registers should be able to calculate change. Press SUBTOTAL once you have entered the items. Now type the amount received from the customer (no decimal point). now press Cash (or other payment key) and the change should be displayed.

To dream that you are taking a bath, signifies a cleansing of your outer and inner self. You are washing away the difficult times. This dream may also be symbolic of ridding yourself of old ideas, notions, opinions, and other negativities. Your dream may be pointing toward forgiveness and letting go.
To dream that you are going bald, suggests a lack of self-esteem or worries about getting older. Alternatively, baldness symbolizes humility, purity, and personal sacrifice. You are at a stage in your life where you are confident in fully exposing yourself.

After entering all of the items for the sale, press SUBTOTAL. Then ask customer for amount on display. Now type in the amount customer gives you (NO DECIMAL POINT) e.g $20 would be 2000 Press the payment type e.g CASH. The change will be displayed

try this
Do this :

key to program,
200 subtotal
press plu button ( or scan product)
type in price ( without decimal point)
press x/time
do next item or press cash to finish