[HELP] Unable to understand the parameters used in the method below

Screen Link:
https://app.dataquest.io/c/11/m/20/logistic-regression/6/plotting-probabilities

My Code:

logistic_model = LogisticRegression()
logistic_model.fit(admissions[["gpa"]], admissions["admit"])

pred_probs = logistic_model.predict_proba(X = admissions[['gpa']])
prob_zero = pred_probs[:,0]
prob_one = pred_probs[:,1]

I am unable to understand that on documentation and screen link it is mentioned that there are two values to be taken/considered i.e. num_features by num_sampleand in documentation it’s mentioned as " X: array-like of shape (n_samples, n_features)" so why are we to use the parameter “admissions[[‘gpa’]]” - > this will return a dataframe only but how it satisfies the condition/state of “n_samples, n_features”?

My response here - Why double brackets? - #2 by the_doctor should clear it up hopefully.