how to download my photos to my computer

See this Apple article: Transfer photos and videos from your iPhone, iPad, or iPod touch

Transfer photos and videos from your iPhone, iPad, or iPod touch to your Mac or PC - Apple Support

(this works on a Windows OS 10 computer) ⤵️

Set iPhone Auto-Lock to Never.

Connect iPhone to computer via USB cable.

Click on 'Allow' on iPhone (when asked).         

Go to start -> All apps.

Click on the Photos app

Click 'Import' at the top right of the screen.

Select 'From connected device'.

Then select Apple iPhone

The Import Items screen opens.

Photos from iPhone appear on screen

Select the photos you want to move to your file by clicking the small square in the photo.

Indicate the folder you want to move them to under 'Change destination'.

And then click 'Import' at the bottom of the blue area. After which the photos will be placed in the folder you chose.

Hope this helps you.