Even Rows and 3 Columns

import numpy as np
import pandas as pd
df = pd.read_csv('abc.csv', sep=',', encoding='utf-8')
df
student language science maths history
0 kumar 90 56 34 34
1 kevin 10 34 32 67
2 sammy 90 23 12 32
3 janice 20 67 90 45
4 peter 30 56 45 65
5 prem 90 45 45 34
6 carrol 50 90 45 23 
df_even = df[::2]
df_even
student language science maths history
0 kumar 90 56 34 34
2 sammy 90 23 12 32
4 peter 30 56 45 65
6 carrol 50 90 45 23 
# Even rows and first 3 columns

df_even_3 = df.iloc[::2, :3]
df_even_3
student language science
0 kumar 90 56
2 sammy 90 23
4 peter 30 56
6 carrol 50 90