Hi @Nikita Pandey ,
Unfortunately you cannot get this information using Microsoft Graph API. You can get the schedules of a User using (/users/{id|userPrincipalName}/calendar/getSchedule) but you cannot get the information if the user is currently in meeting or not using Microsoft Graph API. Please provide it as a feedback at Uservoice so that community can upvote and the product team can plan to include this in future releases.
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