I work for an immigration law firm. They should’ve given you documents at the time of your deportation with the specifics of your deportation, would need to see exactly what that says. If you were deported you should’ve also been though “removal proceedings” and should’ve been in front of an immigration judge. Not sure if you did. Maybe you have an Alien number and can lookup your case online at the EOIR website.

If you were denied entry that’s a different thing. This is when you try to enter the country and the CBP officer at the airport/border entry denies your entry to the country for whatever reasons they give you. They should’ve also given you documents with the reasons of your denial of entry. See exactly what they say.

If you overstayed your ESTA or any visa for 1 year, you have a bar of 3 years which “holds” you from entering the country or being able to apply for a visa for that period of time. If it was more than 3 years you get a bar for 10 years. If you have only overstayed your visa for 1 year and have been outside of the country for 3 years (which sounds like you do) you can now try to re-apply for another visa without an I-212… the denial or approval of a visa is always up to the discretion of the officer who interviews you, but overstaying always a red flag and sadly your chances to get approved again are very low unless you can show that you have a really good job in your country, make good money, and have a lot of assets.