Do you pluck the strings of a forte piano?
No. You play it in a similar way to a modern piano. The hammers (which strike the strings just like in a modern piano) are covered in either leather or felt. Fortepianos usually have a wooden frame rather than the massive iron one of modern grands. The sound they create “decays” more rapidly than that of a modern instrument, which can’t “speak” fast enough to play the rapid passages in the music of composers like Mozart and Clementi without blurring the sound.