@Ayush Shrivastava Thank you for reaching out.
In addition to Sedat SALMAN's answer, you could also use ADF and schedule the execution of the procedure. You can create a pipeline with one or more Stored Procedure activities and add a trigger to schedule the pipeline running. see this https://stackoverflow.com/questions/62417858/run-azure-sql-server-stored-procedure-async
https://learn.microsoft.com/en-us/azure/azure-sql/database/job-automation-overview?view=azuresql
Regarding the second question,
By default, job agents are created at JA100, allowing up to 100 elastic job executions concurrently. Initiating a service level change is an asynchronous operation and the new service level will be made available after a short provisioning delay.
If you need more than 100 concurrent executions of elastic job agents, higher service levels are available, see Concurrent capacity tiers. You can currently change the service level of a job agent via the Azure portal, PowerShell, or REST API.
Exceeding the service level with concurrent jobs will create queuing delays before jobs start in excess of the service level's concurrent jobs limit.