I agree with the previous responses, but would like to add a little twist.
Play the progressive drills. Throw the 7, 8, and 9 on the table. If you run them out, add the 6 and try again. If you run out again, add the 5. If you don't run that one out, remove the 5 and try the 6789 again. Rinse and repeat.
Eventually you'll get to your goal. You'll at least know where you stand, in terms of running out a full rack of nine.
This drill might not "teach" you anything you don't already know. But if you aren't taking lessons or you don't have access to helpful runout players, this is the next best thing. You'll figure it out.
I believe that starting with the last three and working back down to the full 9 (8, assuming you make a ball on the break) will help you explore the longer or more complicated cue ball paths that are sometimes needed in 9-ball. Each additional ball brings exponential difficulty, but you WILL make progress.
Whatever happens, keep playing, keep trying, and keep learning. If there are runout players around your pool room, swallow your pride, and walk over and ask them for help! Most (not all) will gladly give you tips. 9-ball shape/strategy is different than 8-ball, but you'll pick it up quickly.
If you're running out in 8 ball, it won't be long before you get your first "true" 9 ball break and run. Keep it up; that first 9-ball break and run is right around the corner.
Best wishes,
-Blake