Your Tests page only shows tests currently part of your active program. The ⋮ menu → View Additional Tests opens the wider catalog:
Each entry shows its Category (e.g. HR Miscellaneous, Engineering Miscellaneous) and which Frameworks it applies to. Click Add To Program to bring one into your active test set — it'll then show up on your main Tests page like any other test.
Most of what's in this catalog is manual/document-based (upload evidence, checklists) rather than automated integration checks — things automation genuinely can't verify on its own, like an employee termination checklist or proof of infrastructure firewall configuration. Only add a test if it's actually relevant to your business; an irrelevant test just adds noise you'll need to track evidence for.