Full Stack Dev - Update Custom Wordpress Checkout Design

I have a Wordpress Multisite Domain. You can view one of Sub Category pages here: [login to view URL] We created custom checkout and product view. The tasks I need done are the following: 1. When user logs in at checkout screen, he proceeds to next step, and sees fields name, email, phone. The username is appearing in Name field. This is not correct. The Name field is just for name. 2. I'd like to add a Welcome (username) message above the Name field, if user logs in. 3. If user logs in at checkout, menu needs to update to show Log Out instead of Login. (If you test login via menu link, everything works correct, meaning after Login, Log Out shows in menu) 4. When user chooses Register at login, the About Step is being skipped that shows Name, Email, Phone, Ship To option choice, and Site terms checkbox. We need to correct whatever is causing this step to be skipped. (IF you want to see about step page, just click Guest Checkout under login fields) 5. If user chooses Social media buttons to Connect with our site, a new Wordpress user account must be created for them on our server, and then they must proceed to About Step.