How can I import a 2017 Turbo tax file into my computer to complete 2018 using the turbo tax on my computer (from CD)?

Where is your 2017 return?  Did you use the Online version?  I can tell you a couple ways.  Or do you have the .tax2017 file on your computer?

https://ttlc.intuit.com/replies/3302290

After installed 2018 TurboTax in your computer, select new from the left upper top tab "file", the TurboTax will lead you to transfer data from last year return. You need to know where you saved last year return file. Then choose a location to import last year's tax data and continue the work. (I am sorry I am working at office right now and can't attach a screen shot to show you how to do it).  I hope my explanation has a little help for you.