Hi Salma,
Personal Microsoft accounts and Microsoft 365 work or school accounts cannot be merged, but they can be used side by side, check the steps here - https://support.microsoft.com/en-au/office/how-do-i-merge-my-onedrive-for-home-with-my-onedrive-for-work-or-school-85fe5779-dbc8-4c81-abdb-214a3a7d17c6
Hope this helps.
JS
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