Yes, you can modify the RGB colours on the ASROCK B450M STEEL LEGEND.
Yes, you can modify the RGB colours on the ASROCK B450M STEEL LEGEND.
Can I inquire about the CPU you're using? If the budget permits, consider using a B550.
You can choose based on the features and value it provides at that cost. A professional 4 might be a better option using fewer components. Are you restricted to this setup? Also, what are your budget expectations for the board?