Copy the text after @p
from the Command: box. e.g.
/tellraw @p ["",{"text":"This is a JSON text","color":"blue","clickEvent":{"action":"suggest_command","value":"/command"},"hoverEvent":{"action":"show_text","value":{"text":"","extra":[{"text":"Hey there!","color":"aqua"}]}}}]
Copy this part only:
["",{"text":"This is a JSON text","color":"blue","clickEvent":{"action":"suggest_command","value":"/command"},"hoverEvent":{"action":"show_text","value":{"text":"","extra":[{"text":"Hey there!","color":"aqua"}]}}}]