Hello Kamil Włodarczyk,
Thank you for reaching out to Microsoft Support!
Unfortunately, the Graph API currently does not provide an API for connecting to MS forms. As an alternative, you could maintain your own data source of the form response by using LogicAPP or using Power Automate (Formerly Called as MS Flow)
You can refer to this case for details:
https://stackoverflow.com/questions/65697550/call-ms-graph-api-to-collect-online-ms-form-responses
Hope this helps.
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