Hi @Aqua,
Do you want to create an approval and update the Status column in the end?
Could you please share a bit more about the scenario?
Actually, create an approval should use the trigger "When an item is created" which you did is correct. However, you should then add a condition that the Status column is “Complete” to run the following approval process.
I have made a demo for you, please take a try as below.
Here is the complete flow configuration.

1). If a new item is created and the Status column is “Complete” (in my scenario is a Product column). Note that the Start and wait for an approval action will send an email automatically to the people who should approve this request.

2). Add a condition and select Responses Approver response from the list of dynamic values. Select the Choose a value box on the right, and then enter Approve into the box. If the approval approved your request, an email will sent to you.

3). The Status in your SharePoint list should be updated with "Approved".

Here is the test result that how the Start and wait for an approval action send an approval email automatically. Once you approve the request, the Status column will be updated.

Hope it could help you at some degree.