Need a computerized Test banks platform for testing members -- 2

We are an examination body where our members are tested in an examination setting. We test our members based on the knowledge of the training they received. We require a good developer to design and develop a computerized test platform where our members can log in and take the tests in the format created. We want a platform that would have a database of all our questions in different categories per the programs we offer, and then our members can log in, and take the test from the questions in the database. It will be self-grading and at end of the test shows the results to the test takers. We anticipate having a database of over 100,000 questions and answers on this platform. We already have the test questions and answers. The developer will help set up the database in this platform, break and feed the questions into the categories they belong to, and members can take the exams in a computerized setting. The platform will feed each question in a randomized fashion to each member per the program they are being tested on.
We hope to host this database on a server from where only registered members could have access with a login key. if you are a database developer, this is your area

This is an urgent need.