I guess the best is use poly pipe from meter all the way to the kicthen pipe. Than T out from the wall to the tank. This is the most secure from leaking cause by ground movement and impact. No joint at the ground and pressure not drop due to joint. The rest for bathroom and etc, can use PVC. Don't use ABS or PVC for the ground. The glue joint just unsecure enough.

The main pipe is 1" all the way till the tank. The rest I guess is 3/4" or 1/2". This is the original pipe size when brought the house. I didn't modify it beside adding the backup line. For backup line pipe size, I follow what is the main pipe size.

I find back the water supply plan. You can modify it to suit your house. This is an old 14yrs plan.
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1 item you need to modify from the plan is the "water tank inlet tap" to the water tank. Change it to ball valve. You probably don't need the bypass valve and the water filter for the tank. Skip that 1. Add a tap there for tank maintainance. All this is 1" pipe.