HornResp can be used to find an approximation of the ideal horn for a driver based on parameters, but they are generally too huge for practical building. It will be up to you to make the compromises. Also Hornresp will not fold a horn for you. You have to figure that part out for yourself. There are limitations to how hornresp works. it does not think of a speaker as an inverted cone. it thinks of it more as a circular flat disc. It will tell you approximately how much power you can give a speaker before it hits xmax. It will also, with practice, allow you to enter the measurements of a horn design and simulate different drivers in it. I find it fun to geek out on, but it takes some work to get competent with it.
Also worth noting that most simulations are highly inaccurate above the bass range. the tell you how low and loud the bass range is but they don't tell you if it sounds good, nor do the predict the upper range of mids or highs.