You can use the screenshot function that comes with your phone to take a screenshot. Here I will take the phone I am using, Honor 9x, as an example to describe the steps:
Douyin version 22.6.0
1. Open Douyin and find the graphic video of the photo you want to screenshot;
2. On this page, slide the phone screen from top to bottom to bring up the hidden control center page, and click to take a screenshot;
3. Open the photo album on your phone and you can see the photo you just screenshot.
Or you can directly double-click the screen with your knuckles to take a screenshot. The key is that your phone supports this function.