Here's a tutorial on what I think is the best combo lock in Minecraft designed by @Kahyxen. It works in Java, Bedrock, and versions going all the way back to 1.5 the Redstone Update.
More button panels on Discord: https://discord.gg/qXnVhGxH8E
Music from Astro: https://www.youtube.com/watch?v=C9bpCv2qSQM
Redstone Tweaks: https://www.youtube.com/watch?v=jMhlv0AnTmg