Sorry Online is only good for 1 year, the current year. Online 2018 and Efiling closed back on Oct 15, 2019 (over 1 year ago). You have to now use the Desktop program and print and mail your return. Or go to a local accountant or tax place.
Don't you have a full Windows or Mac computer to install the program on? Can you use a friends or family computer?
When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS received the return. Don’t forget state.
Important! Mail Federal and State in separate envelopes and mail each year in separate envelopes.