Is this the way to obtain the same individuals for x_test and y_test?
train_test_split has this capability built-in.  Just pass all of the data in the first go like:

Code:

x_train, x_test, y_train, y_test = train_test_split(x, y, test_size=0.3, random_state=250)


Test Code:

from sklearn.model_selection import train_test_split

x = list(range(100))
y = list(range(100, 200))
x_train, x_test, y_train, y_test = train_test_split(
    x, y, test_size=0.3, random_state=250)

assert(all(xx == yy - 100 for xx, yy in zip(x_train, y_train)))
assert(all(xx == yy - 100 for xx, yy in zip(x_test, y_test)))