Hi Laveena,
When you create a sandbox, Salesforce copies the metadata from your production org to a sandbox org.
you can create a sandbox as following
- From Setup, enter Sandboxes in the Quick Find box, then select Sandboxes.
- Click New Sandbox.
- Enter a name (10 characters or fewer) and description for the sandbox.
- Select the type of sandbox you want.
- Select the data to include in your Partial Copy or Full sandbox.
- For a Partial Copy sandbox, click Next, and then select the template you created to specify the data for your sandbox.
- For a Full sandbox click Next, and then decide how much data to include.
- To run scripts after each create and refresh for this sandbox, specify the Apex class you previously created from the SandboxPostCopy interface.
- Click Create.