Go to Settings -> Storage->SD Card, you can choose Format as internal to format this SD Card. After formatting, it can only be used on your device.
If you choose Move now, the data from the internal storage moves to the SD card immediately.
If you choose Move later, you can move data by going to Settings -> Storage -> SD card -> Migrate data.
After moving the data to the SD card, it will function as the device’s internal storage. Data such as downloads, music, pictures, etc. will be stored on the SD card by default.