You don't file a 1099. Whoever sent it to you filed it with the IRS. You keep the 1099. You REPORT the income on the 1099. You do file W2s, because the IRS does not get copies of those, the Social Security Administration does. When you file those W2s with the IRS, the IRS verifies what you send with what SSA has.
If you never filed for 2016 and 2017, then you file a 2016 return using 2016 forms you can print from irs.gov, and same thing for 2017. (And 2018, if you haven't filed yet).
If you already filed for 2016 and 2017, and you forgot to include the 1099 income and the W2s, then you must file amended returns for those years. You will need a 1040X for both years, also available to print at irs.gov.
You should do it yourself. It's not that hard, and the companies will charge you a lot of money.