execute store result score length func.temp run data get storage func:temp shuffle.list

execute if score length func.temp matches 0 run return 1

execute store result score random func.temp run random value 0..2147483646
scoreboard players operation random func.temp %= length func.temp

function func:shuffle/f2 with storage func:temp {index:0}

execute store result storage func:temp shuffle.index int 1 run scoreboard players get random func.temp
function func:shuffle/f2 with storage func:temp shuffle