To elaborate on the answer given, you are likely going to need to use the AfterUpdate event of the text box or combo box that contains the user input or a value chosen from a list. This you would do via vba code or a macro, but most of us who answer here don't use macros so vba would be our method since it is more powerful and reliable. As for your users, they would not know the difference as long as your method functioned well.
However, the answer implies that you need to delve into aspects of Access design that are likely foreign to you and I would agree on that. It is quite likely that what you should be doing is revealing a hidden subform, or perhaps just revealing hidden form controls for the user to enter data into, depending on prior input. How easy it is for the user to navigate is very much the responsibility of the designer, and that is you. To increase your chances of success in this regard, you should research Access design as much as possible. There are tons of videos and information sites out there.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.