how to choose 5 opcode for 8051 microcontroller

Hi everyone i have project to do with logisim, i need to build a 8051 micrcontroller using 5 opcode or i could choose more than 5 but i have to know which and how to choose .
i want to conect Lcd to the controller so what opcode should i choose with .
thnx

Take a look at this tutorial
https://www.8051projects.net/lcd-interfacing/initialization.php

It gives the code needed to initialise an LCD display.
Displaying a message would need the same instruction set.