What software do you recommend for someone to get started cracking software?
IDA?
Depends on what's your target platform,the type of an app you're going to crack etc.
But in general and at a bare minimum you'll need a disasm/decompiler, debugger and a hex editor.
Then you might want to get some additional stuff like plugins for aforementioned tools, yet again it all depends on your particular target.
If,for example, it is some soft that runs on Win/x64 [and is not a derpy .Net/Unity stuff], then IDA/Ghidra/R2, x64dbg and 010Editor/HxD are good enough
Also some soft might be protected or obfuscated and to make it easier to find out what's going on, you could use DiE for example.
I like that ghidra is free, that definitely makes it easier to work with. Am hoping with enough practice, will be able to decompile and work simple crack exercises.