The closest to vibecoding in the 90's was to open Borland's Turbo C help in any page, copy and paste the example and modify it until you understand it or until it did what you wanted.
You know, that's exactly how I learned to program.
I started up QBasic knowing nothing other than that it seemed like a thing for programming computers and programming seemed like a cool thing to do.
I typed in random words, and eventually I typed "screen". When I pushed enter, QBasic capitalized it, so it seemed important. I hit F1 and read the help. It made no sense, but the example ran and had other capitalized words so I could repeat the process.
Eventually I started making really terrible text-based Final Fantasy knock-offs.
Wow, that’s exactly my memory. As far as my family was concerned I was spending day and night in front of the “blue screen”. I got as far as programming a GUI by copying windows 95 pixel by pixel, text editor, fonts, cd player, minesweeper. I wish I had the code.
The closest to vibecoding in the 10's was to keep searching Stack Overflow for questions vaguely asking similar things as what you wanted and copy-paste things until it kind of worked.
Fairly confident I've never copy-pasted much of any code from stack overflow directly. Shell commands, yes, but code? Usually i just use the answer as inspiration.
Still, you can find an awful lot of solutions there, no question
Turbo pascal help for me! The polynomial example taught me how to use pointers. Before that, I could only use static arrays up to a certain length.
Learning about heap allocation was euphoric. I kept beaming because I had unlocked infinite memory, and people around me didn't get why I was such a happy teenager.
To be fair, I already knew about memory regions from PEEK/POKEing on a commodore as a child, but it was always static and pre-populated.
Microsoft Quick Basic help was also gold.