That's just not how the body works. Most of your training paces need to be based off of your current fitness, not your goal race. That said, if your goal is a realistic one (i.e. is an expected next step from your current fitness), then yes, there are sites that can help you understand what kinds of paces you should be running in workouts. Greg McMillan's site is one example (https://www.mcmillanrunning.com/index.php/calcUsage/calculate).

Again, I caution you against putting in arbitrary goal time and use that to inform your training paces. Doing so leads to injury, burn out, and workouts that are not at all accomplishing their purposes (which, in turn, leads to poor performance come race day).