Which function to select to make sd card default on lenovo phone: Rename, Eject Format as portable or Migrate data?

Migrate data.
That should give the option of moving some things to the card from the phone internal memory.

Not all data or apps are movable, it is down to each app creator if the mark it as being allowed to run from an SD card.

You may have to separately change settings for such as the camera, for where new photos are stored. I know you need to do that on some Android phones.

Also be 100% certain it is a legitimate, branded, SD card, before you do any of that.
A large percentage of memory cards & usb sticks sold on places like ebay are fakes, small ones with the size values changed so things "think" they are larger.

They stop working or lose data once more than the real amount of storage they contain has been filled up.