Ask your organization’s FortiGate admin to download it using their corporate support ID. As an end user, you do not have direct entitlement.
Organizations often retain legacy software versions due to compatibility requirements with older operating systems or legacy management infrastructure. This paper serves as a reference for administrators requiring information on the acquisition and maintenance of this specific build. forticlient version 6010 download link
Despite being released in early 2020, version 6.0.10 remains in use for specific enterprise scenarios: Ask your organization’s FortiGate admin to download it
How to Download FortiClient 6.0.10 (Build 6010): Direct Access & Setup Guide forticlient version 6010 download link
typically provides the most recent "VPN-only" version for free, but usually limited to the current stable branch (e.g., v7.x).