While your loan is in processing, you'll have access to two different web site portals with two different logins (user name and password). The first is called Maxwell. You'll primarily use Maxwell to complete your loan application and upload paperwork like bank statements and paystubs. You may also eSign a few documents using Maxwell and DocuSign.
This is what the Maxwell login page looks like:
Once you've found a house and you're ready to rock and roll, you'll use an Ellie Mae portal to eSign your official legal disclosures. You'll get to go through this process at least three times: once when you eSign your initial Loan Estimate, once when you eSign your "Change of Circumstance" after your loan is locked, and again when you eSign your Closing Disclosure. You don't need to print anything or upload anything. Just eSign.
This is what the Ellie Mae portal looks like: