How do I use my micro 128GB SD card as internal storage on my LG G7 instead of the phones own limited storage? Clear steps?

Hi guys,

I've read that it's better to use a phones internal storage rather than SD cards, only mine is severely limited, which is why I got an SD card because apps are taking up way more space now than they used to. And I never really found a clear answer to my question.

I've inserted my SD card which is blank, I've gone to internal storage to move everything to the SD card but there is no option to do so when I tap the 3 dotted menu for more options, nor is there any option to use the new card as default internal storage. There is only a "show system" menu.

Even when I click the SD card storage format, there's no option to move all apps and such to it. There is only the option to format which I've done already but nothing has helped at all. And all questions I've googled don't answer my question either =\