On the command line the `strings` command will list out printable characters in a file (including compiled binaries).

I don't do any systems level programming but found myself down a small rabbit hole of learning about reverse engineering tools. https://github.com/NationalSecurityAgency/ghidra is an open source one. It will show you the assembly code, does its best at giving you a C representation of that code and lets you interactively rename variables and symbols to make it more human readable.