Hi Chris,
Thanks for posting in the community.
According to your screenshot, I assume you have run agentsetup.exe, connected to tenant in Microsoft 365 Migration. You can view the agent under the Agents tab. Based on the reference and my test, after the agent is configured, please check if you can add source path to scan. If not, please create the task under the Migrations tab, then try to add source path to scan.
Regards,
George