Простой подход
for line in open('myfile.txt').readlines():
a, b, c = line.split()
print(a, b, c)
введите два файла:
with open('1.txt') as f1, open('2.txt') as f2:
for line1, line2 in zip(f1, f2):
a, b, c = line1.split()
d, e, f = line2.split()
print(a, b, c, d, e, f)