They are not keywords, since you may declare a different meaning for them within a block if you wish. You have probably noticed that it does not have any parentheses or numbers after it. Older machines may require you to punch the text on paper tape or cards, but today most machines will handle text files. These are stored in the computer's memory on some magnetic medium such as a disk or tape. You can usually create them by typing them into the system using a text editor.
Machine instructions are different on different types of computer.
This is sometimes referred to as recompiling the program on the second machine. Not all computers require this step. Where linking is not necessary, these standard procedures are found by the command which runs the program. Again you should consult the documentation for your computer for details of how to do this. If your computer currently does not, you may be able to buy one, but they are not available for all computers.