I'd like to say I have a green thumb in that my garden does great as do my plots, but peaches are kicking my butt. This tree is 5+ years old and is supposed to be self-pollenating or whatever (doesn't need a second tree). I've yet to get the first peach off of it. I've sprayed it before with a fungicide, but perhaps I did that at the wrong time of the year. I think I read I should be doing that twice a year? If so, give me some feedback and I'll put a reminder in my calendar. I've tried to prune it, but it's hard to keep up. I did fertilize once or twice with 13-13-13. It does put on small fruit each year, but they rot away.

Google “peach home spray guide”, U of Kentucky has some good info available. Depending on your variety you’ll need to spray several cover sprays plus a dormant and post harvest spray.

If thats a normal sized corn stalk, youre gona need a 12ft ladder to pick your peaches when you get it figured out. My advise is this: growing peaches on one tree in your yard is way more trouble than it is worth. Get peaches from somebody who grows them commercially. But if youre just stubborn and you want to do it yourself, get that sprayguide bamaplowboy referred you to and go by it religiously

Prune that thing. Get some bug spray to. I think I'm just gonna get rid of mine. I prune but the bugs and frost get all of mine. Easier to go the store.

Prunig is needed for sure. Google some images of commercial peach orchards and take a look, they'll show much less green vigorous growth. Quite a few guides for pruning available online too. You will see some talk of "scaffolds" and "fruiting wood" but these start to make sense when you understand the process. Ultimately you're going to want to open that tree up with quite a bit of pruning I suspect.

Peaches also generally benefit greatly from thinning and pruning of the baby fruit down to far fewer per limb. Many varieties are quite precocious and set more peaches than the tree could support. If you only have this one tree it won't be too big a job but it can be tedious. Again there is quite a bit of information available online about thinning the fruit.

Peaches will need spraying to produce good fruit, but it looks like that's been covered.

With some work over the winter and early spring you may just be posting about your first homegrown peach next summer!

You need to eliminate all of the competition around that tree.
And prune it. Would make a world of difference.