Saving and removing players from config.yml

Hi

I need to save players to a config.yml and also remove them. So what would be your suggestions for this?

I have tried a lot of different method but I need to know what would be the best way to do this.

Is it necessary to use YAML? Why not use a list file? (CONFIG_LIST)

And you should use $config->exists($name)

It doesn't really matter if it's txt or yml Which is more efficient?

Text of course

TEXTTEXTTEXT