Create
Go to Customers → New (or New Customer).
Fill company name, emails, phone, tax ID as needed.
Fill the contact block (name / email / phone). The contact email (or company email) is the portal login identity.
Set type (Standard / Wholesale / Enterprise), discount, payment terms days, credit limit, notes.
Save.
Creating with a portal login email usually schedules a portal invite automatically. Details: Customer portal.
Edit
Open the customer → Edit. Prefer inactive over delete when you want to keep history.
One contact block
There is not a multi-contact address book. Use child locations / notes if you need extra people on file.
Locations / branches
Child customers linked by parent show as locations on Overview. Use hierarchy when one company has multiple ship-tos managed as separate records.
List tips
Search company/email/contact · filter type and active · pagination · location counts when hierarchy exists.
Invite portal access from the customer record only when you’re ready for that buyer to see quotes and proofs.