Can I just copy and paste?

I just received this, and have seen so many posts about the SD card but cannot make head or tail of them.

If I just buy a new SD card, put the old one into my laptop and copy and paste everything on there to the new SD card, will this be okay?

I literally bought this just to play the retro Pokémon games, so will not want to download more games or anything.

Never felt my age more! Thank you in advance