One of the most popular methods for creating online quizzes and tests for teacher is using Google Forms with the Flubaroo add-on. I use the same combination for tests which I already have in paper or pdf form. As typing out all questions would be a bit cumbersome and redundant, I actually just use paper/pdf with a Google Forms “answer sheet”, which then will look something like this:
This works particularly well with standardized tests (like the Cambridge English certificates) which use mostly multiple choice, true/false questions. This is a huge time saver, as you don’t have to type the questions themselves and you can quickly create a lot of questions instantly. I do that by copying the number of questions and possible answers from a Google sheet. Say you need 12 questions with four options all you need to do is copy and paste them from the Google sheet.
The students then are sent two links: one to the pdf file containing the test (which can also be printed out) and one to the Google Form to enter their answers. As this kind test is mobile friendly, the students could also use their smartphones to to that.
Using the Flubaroo add-on (there are plenty of tutorial for that) the answers are automatically graded based on a model answer by the teacher. The score and the correct answers can also be sent back to the students. This way an existing test can be quickly turned into an both student and teachers can get immediate feedback.