How does one put floating text like that of servers that utilize plugins to do so? I know you used to be able to do it with earlier than 1.13 with
/summon ArmorStand{Invulnerable:1b,NoGravity:1b,Invisible:1b,CustomNameVisible:1b,CustomName:{"text":"Blocks","color":"yellow","bold",:"true"}} ~ ~ ~
but with the 1.13 update they changed the syntax of this and other commands.
Originally, I tried to "fix it", despite not having ran it, by moving the NBT tags to armor_stand (since ArmorStand didn't exist anymore), but that failed. When I brought it back to the beginning and it summon the object without the custom name either being visible or without having a custom name at all. Which one of those is the issue, however, I'm not sure of.
Best Answer
First error: coordinates go in between the entity name and the nbt.
Second error: the Custom Name needs quotations enveloping the brackets with the name data.
Third mistake: Each quotation within the said brackets must have a backslash before it. Plus, there was a typo in front of "bold" in the command sample you gave us.
A working command: