Blink by github project
First get sourcecode from github https://github.com/sipeed/Tang-Nano-examples
Open led_prj.gprj file in Tang-Nano-examples\example_led\led_prj path
Right click clean&Rerun all in process interface
Then there is an error(This is a historical question, you can search it by yourself if you wonder it)
Change configuration which can be found in Project -> Configuration -> Syntheize of top menu bar and choose GowinSyntheize.
Then right click Place&Route and clean&Rerun all
Connet the board and download firmware.
Program Devicein Process interface to open programmer tool.
Choose download to SRAM to verify codes quickly