Turn on your OPPO phone and enter the home screen.
Locate and open the settings application on the home screen. Usually, its icon is similar to a gear or wrench.
In the settings menu, scroll down and find the battery option.
Click to enter the "Battery" menu, and you will see the information of battery usage.
In the battery menu, you can view the current battery health. Usually, it is displayed as a percentage.
If you want to see more detailed information, you can click the "Battery Health" option. This will display more information about battery life, remaining capacity and so on.
Please note that there may be some differences between different OPPO phone models and operating system versions, so the specific steps for you to check the battery health may be slightly different. The above is a general operation guide, I hope it can help you. If you need more detailed information, I suggest you consult the user manual of OPPO mobile phone or contact the official customer service of OPPO for support.