Postman Tests - Conditioning with http status

This would be something basic that would log that message to the console if the status code was 200:

pm.test('Check Status', () => {
    if(pm.response.code === 200) {
        console.log("It's 200")
    }
})

If you then needed to check something in the response body after, you could do something like the example below.

This is just sending a simple GET request to http://jsonplaceholder.typicode.com/posts/1

The response body of this would be:

{
    "userId": 1,
    "id": 1,
    "title": "sunt aut facere repellat provident occaecati excepturi optio reprehenderit",
    "body": "quia et suscipit\nsuscipit recusandae consequuntur expedita et cum\nreprehenderit molestiae ut ut quas totam\nnostrum rerum est autem sunt rem eveniet architecto"
}

We can add a check in the Tests tab, to confirm that the id property has a value of 1, it would only run this check if the response code was 200:

if(pm.response.code === 200) {
    pm.test('Check a value in the response', () => {
        pm.expect(pm.response.json().id).to.eql(1)
    })
}

This is a very basic and a very simple example of what you could do. It would be more complex depending on your own context but hopefully it explains how you could do it.