Need help!

Welcome to the forum Brian. That build looks fine to me, just make sure you factor in the OS as well if he doesn't already have a valid Windows 10 license to use. Another thing to keep in mind is that the Ryzen 3 3200G's memory controller supports up to DDR4 2933mhz memory, and going beyond that isn't a guarantee that the memory will work. If you can save a little extra by going with slightly slower memory, I would recommend doing so as it will save you the headache of adjusting memory timings to make it stable. 

These are a few bucks cheaper and should be easier to run in order to maintain stability:
https://www.microcenter.com/product/608784/crucial-ballistix-sport-lt-16gb-(2-x-8gb)-ddr4-2666-pc4-21300-cl16-dual-channel-desktop-memory-kit-2k8g4d26bfsbk---gray
https://www.microcenter.com/product/474187/gskill-aegis-16gb-(2-x-8gb)-ddr4-3000-pc4-24000-cl16-dual-channel-desktop-memory-kit-f4-300c16d-16gisb---black-red

If you have any other questions, please let us know!