I see! Well, it depends. If you want advice for competitive sets then you'd open up a thread in there. If you want advise for a regular ingame set then you can ask in Previous Generations (if it's from an older game) or if it's from SwSh then you'd ask in there.
There aren't any general Q&A threads so making your own one if you have a question is the best way to go about it. ^^