The CPU is practically an i7-4770 without integrated graphics and with ~3% less performance (lower clocks).
My brother is suggesting that I go for an AMD build and go for the 8350 because "it has more cores and higher clock"... what does this mean and what makes the intel i5 better? Kinda new to this area.
Watch this, it explains cores and threads pretty well: https://www.youtube.com/watch?v=wnS50lJicXc
As far as clock speeds go, you can't really compare AMD and Nvidia (Intel has stronger cores).
The FX-8350 is about equal to the i5-4670k, so the Xeon E3-1230 V3 should be a lot stronger than the FX-8350.