Enderman commands

First of all, you need to run the following commands in the chat in order to make any of this work:
/scoreboard objectives add teleport minecraft.used:minecraft.carrot_on_a_stick

To give yourself the enderman head, run this command (it's long enough that is has to be put into a command block):
/give @p minecraft:player_head{AttributeModifiers:[{Slot:"head", AttributeName:"generic.maxHealth", Name:"generic.maxHealthg", Amount:20, Operation:0, UUIDLeast:1, UUIDMost:1}],SkullOwner:"MHF_enderman",tag:"enderman",display:{Name:'{"text":"Enderman Head","color":"dark_purple"}'}}

The following commands should always be running on a loop. The order of the commands within each section should be the same, but the sections themselves can be put in any order, run in separate chains, or omitted if you don't want the effect.

Give the teleport stick when you put on the helmet:
/execute as @a unless entity @s[nbt={Inventory:[{Slot:103b,tag:{tag:"enderman"}}]}] run tag @s remove givenStick
/execute as @a unless entity @s[nbt={Inventory:[{Slot:103b,tag:{tag:"enderman"}}]}] run clear @s minecraft:carrot_on_a_stick{display:{Name:'{"text":"Teleport","color":"dark_purple"}'}}
/execute as @a[nbt={Inventory:[{Slot:103b,tag:{tag:"enderman"}}]}] unless entity @s[tag=givenStick] run give @s minecraft:carrot_on_a_stick{display:{Name:'{"text":"Teleport","color":"dark_purple"}'}}
/tag @a[nbt={Inventory:[{Slot:103b,tag:{tag:"enderman"}}]}] add givenStick

Teleport stick makes you teleport:
/execute at @a[scores={teleport=1},nbt={SelectedItem:{id:"minecraft:carrot_on_a_stick",tag:{display:{Name:'{"text":"Teleport","color":"dark_purple"}'}}}}] run tp @p ^ ^ ^16
/execute at @a[scores={teleport=1},nbt={SelectedItem:{id:"minecraft:carrot_on_a_stick",tag:{display:{Name:'{"text":"Teleport","color":"dark_purple"}'}}}}] run spreadplayers ~ ~ 0 1 false @p
/execute at @a[nbt={Inventory:[{Slot:103b,tag:{tag:"enderman"}}]},scores={teleport=1}] run playsound minecraft:entity.enderman.teleport master @p ~ ~ ~ 1 1
/scoreboard players set @a teleport 0

Autododge arrows:
/execute at @a[nbt={Inventory:[{Slot:103b,tag:{tag:"enderman"}}]}] positioned ~-0.8 ~-1 ~-0.8 if entity @e[type=arrow,dx=1.6,dy=2.5,dz=1.6,nbt={inGround:0b}] run spreadplayers ~ ~ 0 16 false @p

Damage from water:
/execute at @a[nbt={Inventory:[{Slot:103b,tag:{tag:"enderman"}}]}] if block ~ ~ ~ water run effect give @p minecraft:instant_damage
/execute at @a[nbt={Inventory:[{Slot:103b,tag:{tag:"enderman"}}]}] if block ~ ~ ~ water run playsound minecraft:entity.enderman.teleport master @p ~ ~ ~ 1 1
/execute at @a[nbt={Inventory:[{Slot:103b,tag:{tag:"enderman"}}]}] if block ~ ~ ~ water run spreadplayers ~ ~ 0 16 false @p

Some questions that I know people are inevitably going to ask:
Why don't you take damage when it rains?
Because I don't know how to detect when it rains. If you do, let me know.
Why am I not tall?
Similarly, I am not really sure how I would make that happen, but I'm open to advice.
Isn't this overpowered?
Yeah probably but I made it just for messing around in creative, not necessarily for survival gameplay.