Acoustic-electric guitars do not require special strings. You can use the same strings as you would on a traditional acoustic guitar. The built-in pickup in an acoustic-electric guitar is designed to work with any standard acoustic guitar string.
However, some players prefer to use strings that have a little more ‘bite’ to them, so they can be heard more clearly over the amplification. In such cases, strings with a thicker top layer of phosphor bronze, or strings that are specially designed for low-end reinforcement, can be good options. But remember, it all boils down to your personal taste and what sounds best to you.