In Photoshop, there's a fantastic and highly useful tool called Smart Object. If you're unfamiliar with this tool and how to use it, follow along with the article below.

1. What is a Smart Object?
Smart Objects have been integrated since Photoshop CS3, evolving and improving with each version. Despite their usefulness, many users overlook this tool.
Essentially, a Smart Object is an intelligent entity housing original data of a layer (text, image, vector). Moreover, you can manipulate Smart Objects with Transform and apply Filters without altering the original attributes of the layer.
Distinguishing between regular layers and Smart Objects can be done through their respective icons. If you spot the File icon atop a layer as shown below, it indicates the layer is a Smart Object.

2. Converting Between Regular Layers and Smart Objects
Step 1: Simply click on the layer you want to convert into a Smart Object.

Next, go to the Layer (1) menu => Smart Objects (2) => Convert to Smart Object (3).

After converting to a Smart Object, you'll notice the icon at the corner of the Layer as shown below.

Step 2: To convert a Smart Object back to a regular layer, click on the Smart Object layer (1) => Layer (2) => Smart Objects (3) => Rasterize (4).

3. Adding an image into Photoshop and automatically converting it to a Smart Object
Step 1: Click on the File (1) menu => Choose Place Embedded (2).

Next, select the image file (3) => Click Open (4).

Then, adjust and drag the image to your desired position and press Enter to confirm.

Afterward, you'll see the layer converted to a Smart Object.

4. Changing template style while preserving format using Replace Contents
This feature allows you to store the original information of the layer and apply it to another template image. Here's how:
Step 1: Right-click on the Smart Object layer (1) => Choose Replace Contents (2).

Next, select the image from your computer (1) => Click Open (2).

Step 2: Adjust and move the image to your desired position, retaining any pre-existing effects and filters.

With the insights shared about Smart Objects in this article, you can see how valuable this feature is and how it can assist you when needed. Wishing you all success!