I learned to code with Turbo Pascal 6 without the internet by trial-and-error and the debugger. When in real mode, a program crash would often reboot the system or occasionally lead to some other unexpected behavior/semi-silent corruption.

Borland C++ 3.1 & Application Frameworks for DOS and Windows 3.1 came with an entire library of paper books. It was probably the heaviest and largest boxed retail software package ever because 4.0 skimped on paper books and didn't include real mode versions of the IDE for DOS.

The Pascal almost equivalent was Borland Pascal 7.0 with Objects.

It was possible to link assembly, C++, and Pascal in the same executable assuming the memory model and function calling convention were set correctly.