TypeError: string indices must be integers

[snippsat]

Some advice can simplify the dictionary be using enumerate() then no need to hardcode Question1,Question2....,
then also can remove i = 0.
Also if using function it look cleaner.
Example.

def questions():
   return {
       "What is the capital of France?": 'Paris',
       "What is the capital of Germany? ": 'Berlin',
     }

def quiz(questions):
    score = 0
    for quiz_numb, question in enumerate(questions.keys(), 1):
        answer = input(f'Question.{quiz_numb}\n{question} ')
        if questions[question] == answer:
            print('Correct\n')
            score += 1
        else:
            print(f'Incorrect the answer was: {questions[question]}\n')
    print(f'Total score for this round: {score}')

if __name__ == '__main__':
   quiz(questions())

Output:
Question.1
What is the capital of France? Paris
Correct

Question.2
What is the capital of Germany?  Bern
Incorrect the answer was: Berlin

Total score for this round: 1