Add REST web service to Get/Update some profile information and course data from LearnDash plugin

We are using a LearnDash Wordpress plugin for e-learning part of our website. We would like to add REST web-services functionality to our Wordpress installation with the following functionality: 1. Log users in (securely) 2. Retrieve/Update user data (name, surname, password, dispaly_name) 3. Retrieve list of LearnDash courses assigned to the user + course descriptions + user progress 4. Retrieve list of lessons assigned to a particular lesson + lesson description (html) + user progress 5. Update user progress when they complete a given lesson. Please only apply to this project if you have experience with the Learndash plugin. Important: You will need to give us the list of any files that have been modified and describe modifications done to it. Please keep a log of any changes to the core files of any plugins, we will not complete the project without these.