Hello Ebrahimi, Shiva, the free services that you get as part of the Azure for students is the B-series VMs only which does not have GPUs on VM. The GPU-optimized VMs are the N-series VMs which aren't part of the free SKU. See the below screenshot.
This means that for the N-series GPU-optimized VMs, you can leverage the $100 credit that you get as part of this subscription. Reference: https://azure.microsoft.com/en-in/free/students/
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