Missing Picture Program

I have been using a photo program which I somehow seem to have lost from my computer. I thought it was called Windows something but now when I go into my photos it's Windows but a different one. I'm non techie and have been into my programs but can't see the one I have either lost or is now not the default one. I will try to download a screenshot of the prog I have lost - perhaps somebody can ID it for me and tell me how I get it back because I am so used to it now to work on my photos. I have tried to upload a screnprint as an attachment .
If at hasn't workedI don't know whether this will help identify it but the big photo comes up on the left and to the right it says Crop and Rotate Under this is Enhance or Adjust Under this a series of square alternative filters - 6 or 8 of them If above I hit Adjust I can change the light or Colour or a button for Clarity I have Windows 10 Thanks

Brink said:

Hello skysurfer, :)

That would be the "Photos" app in your screenshot.

If you wanted to set it as the default app, then you could use an option in the tutorial below to do so if "Photos" is still installed on your PC.

Choose Default Apps in Windows 10 - Windows 10 Apps Features Tutorials

Thanks for responding Brink.
When I go to that link it says there are several options and I don't know which is the one I need.
I think it may all be too complex for me.
Which option do I go for please?

How can I check if Photos is still on my computer?
Where would I fnd it?
If I download a new one -would it tell me if I already have it?

How do I get to Settings and that System page?
I found a settings from the help at the bottom but that looked different to the Systems pages below...
Sorry to be dense
Skysurfer

THANK YOU I HAVE USTMANAGEDTO DO T ALL
Thanks so much
OPTION THREE
To Choose Default Apps in Settings

1. Open Settings, and click/tap on the System icon.
Note
Starting with Windows 10 Creators Update build 15002, you will need to click/tap on the Apps icon in Settings instead.





2. Click/tap on Defaults apps on the left side, click/tap on an app type (ex: Web browser, Email, Music player, Video player, Photo viewer, Calendar, or Maps), and choose an app to be the default. (see screenshots below)
Note
Look for an app in the Store = Will open the Store (Beta) app for you to select and install an app to open the app type with.