[1.21.5] My Datapack is not multiplayer friendly, i need help.

Im Making a Horse Racing world with customly made datapack, it's my first time making a datapack, and ive made this: ' # position calculating execute as @e[tag=racer,limit=1] store result score @s ponsX run data get entity @s Pos[0] 1000000 # accel amount execute as @e[tag=racer,limit=1] unless score @s posX = @s posXPrev run scoreboard players add @s accel 3 # accel limit execute as @e[tag=racer,scores={accel=54..},limit=1] run scoreboard players set @s accel 50 # position reset execute as @e[tag=racer,limit=1] run scoreboard players operation @s posXPrev = @s posX # accel remove execute as @e[limit=1,tag=racer,scores={accel=1..}] if score @s posX = @s posXPrev run scoreboard players remove @s accel 1 # # Effects! # execute as @e[limit=1,tag=racer,scores={accel=10..30}] run effect give @s speed 1 0 true execute as @e[limit=1,tag=racer,scores={accel=31..49}] run effect give @s speed 1 1 true execute as @e[limit=1,tag=racer,scores={accel=50..}] run effect give @s speed 1 2 true execute as @e[limit=1,tag=racer,scores={accel=50..}] at @s run particle minecraft:white_smoke ~ ~ ~ 0 0 0 0.1 1 force ' As i've said, its my first time, i need it multiplayer friendly. The mobs tagged with racer, are horse like mobs (Horse, zombie horse, skeleton horse, mule, and donkey) The system works only for one player at a time I made it execute in tick.json