Hi Balaji Venkatraman Srinivasan(UST,IN)
You might not have quota to NC24ads_A100_v4 compute quota in AML studio
You can follow the below steps in below thread to raise quota from quota team side or directly raise Subscription/quota to avail the needed quota
You can also attach an external NC24ads A100 VM from attach compute option post it is created (As Andreas suggested)
Thank you