Computer died, does adobe cloud store my catalog?

If you’ve been working with a catalog folder and file, that’s Lightroom Classic, where all photos and their catalog are stored locally on your computer. Because they are locally stored, it’s the responsibility of the user to make sure the catalog gets backed up. Lightroom Classic does have an catalog backup feature (the command Lightroom Classic > Catalog Settings, Backups tab), so if you had enabled that, just go find the folder where Lightroom Classic was backing up your catalog at the end of each session. If you had not enabled that, then the catalog would be backed up only if you are running other backup software, such as Apple Time Machine, that makes regular backups of your Mac system. 

If you’ve working with photos and never had to think about the catalog, and if there was no Module Picker at the top, and no Print command, then you’ve been using cloud-based Lightroom. For cloud-based Lightroom, there’s no local catalog to back up, but that would mean when you open Lightroom all your photos and organization should always be there, because they’re not affected by anything that happens locally.

If you were using cloud Lightroom, then it wouldn’t matter if your computer died because all of the photos you imported would be in the cloud and accessible from any other device that you can use to sign into Creative Cloud, like an iPhone, an iPad, or another Mac or Windows computer with Lightroom installed and signed in, or in a web browser at lightroom.adobe.com . So for example, if you walk up to any computer, go to lightroom.adobe.com, and sign in with your Creative Cloud account, and all your photos show up on that private web page, then you were using the cloud version of Lightroom and never had a local catalog. But if you sign into lightroom.adobe.com and you either see no photos, or you only see a few photos/videos*, then you were probably using Lightroom Classic and the catalog was on your computer. 

*which were manually synced up from Lightroom Classic collections or shot in the mobile apps

What Plan do you pay for that gives you 100GB?- 

And what Version Number of 'Lightroom' are you using?

Lightroom-Desktop (the Cloud version ) does store catalog and photos in the Cloud, but we need to know which app and version you are using.

Using Lightroom-Classic: Without backups of your Catalog AND Photo files, I am sorry to say you are "screwed".

Lr-Classic can backup the Catalog when you exit the app- depending what you have set the options for in Catalog preferences. (Every time, Once daily, Once weekly, etc), however it must by on a separate hard-drive that has not been lost with the computer crash. If you don't have catalog backups in zip file then all your editing and work is lost.

Backing up the Photo files is your responsibility- Lr-Classic does not back them up in any way. Again, they must be available on a separate hard-drive.  If your photos were only stored on a drive that crashed then all your photos are gone.

To be curt- Lesson learned.