How to clean windows without leaving streaks?

Try good old soap and water. Like Dawn or similar. Then rinse well. After that try Windex, or alcohol and water for the final. Use newspaper to wipe them. (if you don't get the paper use cheap paper towels. I agree that you have a film on them and it might just be from Simple Green, it is a fantastic cleaner but not for windows or shiny things.

Have you tried a vinegar water solution? That's all I ever use. And newspaper, 100% cotton cloth or a microfiber cloth.

I have my windows professionally cleaned spring and fall and I do them monthly in between or as needed. I have pets so some, like the sliding glass door, that gets cleaned every few days.

I like using a 1/1 vinegar/warm water solution and then wiping dry with wadded up black and white print newspapers. I think this gets my windows the cleanest with no streaks. Not to say that I don't get an occasional steak but I just use the vinegar/water/fresh newspaper to clean again.

Did you first wash with a mix of hot water and a few drops of Dawn dish liquid?

Rinse, then wipe dry.

Did you use a squeegee to remove water, wiping from top to bottom, overlapping strokes, and wiping squeegee dry after each stroke?

Using a lint free rag is possible, only if it has never been laundered with fabric softener, but a good quality squeegee is much faster and will do a better job.

If these windows were inadvertently sprayed with liquid lawn treatments, etc., you will need to remove any trace of these items, first.

Here's a post that might help https://chascrazycreations.com/eco-friendly-window-and-mirror-cleaning/

First, take an equal amount of vinegar and water and mix them together in a spray bottle. White distilled vinegar will work best for this. Then, spray the solution on your windows and let it sit for around two to three minutes. Lastly, use a gentle cloth to wipe away the cleaning solution and avoid any streaks.