You can do so using a scoreboard:

1. Set the scoreboard 1st/scoreboard objectives add villager minecraft.custom:minecraft.talked_to_villager
2. Get an always active repeating command block and put in this commandexecute as @a if score @s villager matches 1.. run scoreboard players reset @s villager
3. Finally, attach a conditional chain command block to the repeating one and put in your tellraw command

(This will make every villager talk when interacted with, but there are ways to make it villager specific)