@Anil Guliyaan Thanks for clarifying.
Regarding the below ask:
The above window makes a call to Events - List By Subscription Id. You can collect the fiddler traces or use the browser F12 traces and check it. See the below screenshot from my machine:
If you want to filter based on the region, then it should be passed as a filter=region eq 'West US' as shown below. But the request should be done either using Subscription ID or Tenant ID.
GET https://management.azure.com/subscriptions/subscriptionId/providers/Microsoft.ResourceHealth/events?api-version=2022-10-01&$filter=region eq 'West US'&queryStartTime=7/24/2020
Hope this answers.