How to kill a certain player from a group when they have scoreboard value?

I'm developing Squid game, and I'm currently on Red, Greenlight. 4 of my friends will join.
The code I'm using is making a scoreboard and if it passes the fake player's point -> kill
The code is like this: (jump test)

scoreboard objectives add isjump minecraft.custom:minecraft.jump
scoreboard players set #JumpReq isjump 1
setblock 209 25 -495 minecraft:redstone_block(this activates the killing block)
execute if score MyName isjump >= #JumpReq isjump
kill Myname
scoreboard players set Myname isjump 0

As you can see, it can only kill a player that has name on the command block. I want to kill players when they are in the right status, not typing the name at the code.

I don't think your code runs at all... your 4th line is missing run <command>.

Your titles asks to kill a player with X score:

execute as @a if score @s isjump matches 1.. run kill @s