Hello, I have a DE10-Nano development board and am trying to create a program that has a UART that receives data from a PC hyperterminal and then toggles 1 LED or another based on the received data. Where should I start?

Hello Welcome to INTEL forum. The DE10-Nano Board belong to Terasic. It would be better if you could contact Terasic for enquiry related to Terasic board. https://www.terasic.com.tw/cgi-bin/page/archive.pl?Language=English&CategoryNo=12&No=20 Please accept my apologies for not being able to assist you fully as this is out of my expertise.