Seamless Outlook-to-Gmail Migration

I need every one of our 60–70 k Outlook messages, complete with their attachments, moved into Google Workspace while keeping the same email address active throughout the process. The single most important... (Budget: ₹600 - ₹1500 INR, Jobs: Data Backup, Excel, Microsoft, Microsoft Access, Microsoft Outlook, Project Management, Scripting, Technical Documentation)