You can teach 8086 assembly which is still compatible with modern x86 and it only has like 20 instructions. It's lots of fun I made a whole bootable text editor an assembler and an almost finished lisp interpreter too.
While I have seen many claims that the 8086 has more than 20 thousand instructions that is very silly. By the same criteria any RISC with fixed 32 bit instructions would have 4 billion of them.