The USB-C to Lightning is technically superior and so should be your priority. The maximum supported by the iPhone family is 20W with USB-C to Lightning, while the maximum supported by the iPhone family is 12W with the USB-A to Lightning.
You do need a modern iPhone to take advantage of the difference.
But these two cable types do both have their roles. A USB-A port is slightly lower cost, so you may save a few $ in total combined with it. That may have role like in say keeping an iPhone charged when speed to recharge is not a requirement.
And you really REALLY need to focus on the port types. USB-C is the round oval type and USB-A is the rectangular chunkier type.
The 65/4 Atom has 3 USB-A but only 1 USB-C. So you may find you do actually want both cables if say you had an iPad or a laptop which wants 45W USB-C and you give the iPhone the USB-A 12W port. If your iPhone recharging as fast as possible was your priority then you’d use USB-C to Lightning cable in the 65/4 USB-C port, but if then later you wanted to recharge an iPad or a laptop, you may then want to move the charged iPhone to the USB-A port and use a USB-A to Lightning cable to keep the iPhone charged.
So you may want to buy both cables so you can tune the connections to the daily needs.
As of right now, you should buy the USB-C to Lightning cable but later you may find you want to also buy the USB-A to Lightning cable to use the 65/4 USB-C 45W port for something more needing 45w than the Iphone needs 20W.
It’s a good idea if you have cables ending in the same connector type, to buy different colour cables so you don’t have to retrace the cable’s source. A good method is to use a red cable for the fastest charging so you can remember “red = fast”. But if colour choice has a cost consequence you can just put some mark like a coloured tape on the fastest cable.