****STEP 1 → Buy 5 .com domains (we recommend Cloudflare.com for best prices).
STEP 2 → Connect domains to your hosting (we recommend 20i for best prices).
STEP 3 → Create 2 emails per domain (10 emails in total).
STEP 4 → Connect all emails to one Gmail for easy management.
STEP 5 → Add MX + SPF, DKIM & DMARC records to each domain.
If you prefer to be inside of Google Workspace ecosystem you can follow THIS guide. Just to let you know that this can be costly (18$/month per inbox).