The CRM app installs contacts, companies and a deal pipeline, already connected.

Open the launchpad and install CRM. It creates its own space with the sheets and views set up.
The default stages are a starting point. Change them to the stages you actually use — the words your team says out loud in a pipeline review. A stage nobody can define is a stage that collects deals forever.
Keep the list short. Six stages is usually enough, and each should mean a real change in the customer's commitment, not just internal activity.
Group by stage and drag deals across as they progress. The column counts show where deals accumulate — which is the most useful thing a pipeline tells you.
Add a close date and an owner and you can filter to what is closing this month, and whose it is.
This is where CRM in a work platform beats a standalone one. Link a deal to the project that follows it: when it closes, delivery already knows what was sold, by whom, and on what terms — no handover document, no re-typing.
A Relation to your projects sheet is all it takes. See Relations, mirrors and rollups.
Related: Apps and the launchpad · Board view · Automate the repetitive parts