How do I install four Adobe products that I purchased into four different computers?
I'm not sure what you are asking. You simply install them from scratch on every machine using the specific serials. If you mean something else, you need to explain better and in more detail.
One of the products is going to be installed into a computer that will
be replaced in a few months. Can it be transferred to the new computer?
You can install and activate Adobe Products only on 2 machines at a time. In case you need it on more machines either buy a new license for the product or uninstall and de-activate Adobe product from the old machine and install it on the new one.