Lightroom and photoshop stopped working

MACOS Sierra v10.12.6

I assume your MAC  cannot be upgraded to a newer MACOS?

• LrC v12 requires MACOS Big Sur v11 or later
• LrC v11 requires MACOS Catalina v10.15 or later
• LrC v10 requires MACOS Mojave v10.14 or later
• LrC v9 requires MACOS High Sierra v10.13 or later
• LrC v8 requires MACOS Sierra v10.12 or later,
• LrC v7, and v6 requires MACOS El Capitan v10.11 or later.

in case I wrote something down in error, that info from:

https://helpx.adobe.com/lightroom-classic/system-requirements.html

and

https://helpx.adobe.com/lightroom-classic/system-requirements/earlier-versions.html

If you subscribe to a Adobe Plan, then you should have at some point, installed the Adobe Creative Cloud Desktop App. On a MACOS that app should show up as an icon on the top bar.

Is that showing up? And if you bring that up, are you signed in?

Pay attention to any messages that might pop up when you sign in. Particularly to any involving updating the app.

Warning/ Only install the Adobe Creative Cloud Desktop App if you pay for an Adobe Plan, if you subscribe. Do not install that app if you are using the older pre subscription perpetual Lr that ended at v6.14 (six dot fourteen)

Note/ In the Adobe Creative Cloud Desktop App, the available versions of the various applications will only show updates that your OS and computer will support. Hence if you are running MACOS Sierra v10.12.6, you will not see anything newer than LrC v8.

Important/When you sign in to the Adobe Creative Cloud Desktop App, the e-mail address must be the same address you used when subscribing to your Adobe plan. That can be looked at by going to adobe.com, signing in, and looking at the management of your account/plan.

followup/ Your Adobe Creative Cloud Desktop App may be out of date. As you appear to be coming from way behind the update/upgrade curve, several updates have occurred over time including at least one where an older version failed to show CC app updates.

I have/had Lightroom cc 2015