how to make floating text 

like example in this one:

 

/botadd <name>
/nick bot <name> &fFreeBuild

/model bot <name> 0

 

Then you can mess with /modelscale bot <name> Y 1-2 to adjust its height

it worked

Basically what @aleksb385 said, but I do not recommend since some people will not see the text at all if they changed their client settings.

You can also do this: (example)

/botadd FreeBuild

then

/model bot FreeBuild block

Ok good!