In lieu of this, Nand2Tetris [1] is an absolutely great online, free course where one can go through all of a computer's abstractions - logic gates to an assembler to a bytecode compiler to a stack based virtual machine with an interpreter and an operating system with display, I/O, etc, building everything along the way yourself.
The hardware stuff is in a simulator of course, but that doesn't take away from the gold mine of revelations one gains from going through this course.
The community is great as well, so many people did amazing things like build entire ray tracers in their own computer. Although I stopped at a sudoku game, seeing all of that is so good.