What's your question? Ask

It will die back naturally at the end of autumn.

Your peonies have powdery mildew. This article will help: https://www.gardeningknowhow.com/ornamental/flowers/peony/powdery-mildew-peonies.htm

There could be several reasons why it won't set bloom. They need as much light as you can give them, and an occasional feeding. Here is a link for more information: https://www.gardeningknowhow.com/ornamental/flowers/peony/why-your-peony-buds-but-never-flowers.htm

Peonies send up new shoots from the ground, not from last year's growth. If the leaves now longer look good, go ahead and cut it down. I leave one or two inches of stem to mark where the plant is located. If the stems have botrytis spots, remove all infected parts. Clean the area well so disease doesn't overwinter in plant debris.

I do believe this is the best move. It is very possible to move, and even divide them. Here is an article that will help: https://www.gardeningknowhow.com/ornamental/flowers/peony/dividing-peony-plants.htm

This article will help you:
https://www.gardeningknowhow.com/ornamental/flowers/peony/peony-pruning.htm