No, the Intel graphics will be used on light tasks like windows apps, web browsing, etc...
You use Win. settings to switch to the RX640 for gaming or other heavy tasks.
My PC- Ryzen 5 5600x, B550 aorus pro ac, Hyper 212 black, 2 x 16gb F4-3600c16dgtzn kit, NM790 2TB, Nitro+RX6900XT, RM850, Win.11 Pro., LC27G55T.