Is the component not available to select on your page editor layout?  It should be.  I have successfully added it to several custom objects in our org

Thanks for the reply, Chris! It’s only available on the account page layout and account lightning page editors. I’m fairly new to the org and it looks like the package was installed years ago, so I’m wondering if it needs to be updated?

Thanks for the reply, Chris! It’s only available on the account page layout and lightning record page editors. I am fairly new to the org, and the package was installed quite some time ago, so I’m wondering if the package needs a refresh or update?

Of course!
Yes - I think that is a good place to start by seeing if you need to update your version of the managed package.
Once complete you can go to the Box app in your app launcher and then Box Settings > Advanced Setup > Add Box to Page Layouts

that page should give you some assistance on this initial setup. You can also go to the support page - https://support.box.com/hc/en-us/sections/21356626314643-Box-for-Salesforce
for more instructions/details on the integration.

Hopefully that gets you up and running. If not, let us know and I am sure someone can provide some help.

By chance - are you trying to add it to a page in Salesforce Classic?  I just noticed that in your response.  I don’t have any experience with that if that is your use case.  Our org is fully lightning.  So my advice may not be of much help.  But I would update the package if possible either way, if it was me.

We’re in Lightning as well! Looks the package just needed a refresh. I’m seeing it available on all of our custom objects now. Thanks for the help Chris!