import numpy as np
import random
m,n,p=5,5,4
arr=np.zeros((p,n,m))
def insertingArray(arr):
for k in range(p):
for i in range(m):
for j in range(n):
arr[i][j][k]=random.randint(1,10)
insertingArray(arr)
print(arr)
This is the output after running.

>Solution :
You confused with the sizes so you get index out of range error
try:
import numpy as np
import random
m,n,p=5,5,4
arr=np.zeros((p,n,m))
def insertingArray(arr):
for k in range(p):
for i in range(n):
for j in range(m):
arr[k][i][j]=random.randint(1,10)
insertingArray(arr)
print(arr)