How do I add enchants along with name in command block [duplicate]

It seems to me that you have malformed nbt. In all the commands you’ve tried, you opened an array and never closed it. What you’ve done.

Enchantments:[{id:"minecraft:knockback",lvl:1000s}

What the correct way is.

Enchantments:[{id:"minecraft:knockback",lvl:1000s}]

Notice in the bottom example there is a close bracket at the end and the top example there isn’t. That is an example of malformed nbt. Your final command is below.

/give @p minecraft:lead{display:{Name:"{\"text\":\"Test Name\"}"}, Enchantments:[{id:"minecraft:knockback",lvl:1000s}]}

For later problems I suggest using mcstacker to generate commands.