The machine had a dead tape-deck on arrival, which meant that we couldn't play with any of the games in the bundle (10 IIRC).
My sisters lost interest pretty much immediately, but I read the manual and started entering the simple BASIC programs.
Over time I learned BASIC pretty well, eventually moving on to z80 machine code.
I stopped programming for a few years, instead preferring to play games, but then I wanted to get extra-lives so I started "hacking". Slowly learning how to by-pass the loaders on commercial games, so I could examine the programs and tweak them for infinite lives, timers, & etc.
I got a few POKEs published in UK magazines at the time, you'd write a little BASIC program that POKEd in machine-code to load the game from tape, patching it to return to your control, before modifying the game-code and jumping to the entry-point.
That occupied me from 84-90 or so.
Some to learn, some to work, some for a hobby.
At work on that period, I've used 68000 assembler, S35 assembler, Microsoft Basic, LightSpeed Pascal, C, Modula-2.
In the 90's personal computers became more powerful, internet became accessible, and therefore the gamut of accessible programming languages became much wider and much more interesting (Lisp, scheme, prolog, ML, Ada, Modula-3, Oberon, etc). But that's not your question.
Then moved on to Z80 assembler (massively faster, and that's where you really get to understand how the computer works).
At the end before going to University also used some Pascal, but not that much.
Didn't know about C back then, wish I had.
It didn't have a floppy drive, but it did let you save your programs to an audio cassette tape so you could load them up and reuse them later.
This was a highly unreliable way of storing programs, as my sister would often record audio over my programs because she liked watching the needles on the tape recorder move back and forth as she spoke.
Several others that I've forgotten.
TI-99/4A: Logo and BASIC
Apple II: Applesoft BASIC and 6502 assembler
Commodore Amiga: BASIC, ARexx, assembler, Pascal, Aztec C.