Terminal syscalls in Assembly

I would like to write a chess engine for Linux. It will be in pure X64 Assembly language without any C/C++ or any other high level languages external libraries. It will run in full screen text/console/terminal mode. No GUI. It will use Unicode characters to display the chess pieces. I know how to make it in Windows Console API. Which Linux kernel syscalls are relevant to directly access the terminal and to change the font to one that supports Unicode? I obviously researched it but found very little info, mostly for 32 bit with int 0x80 calls.