What is the quickest way for me to bring a person to the US?

If she overstayed in the US by 7 months but she entered the US lawfully, once she leaves the US she will be barred from reentry for 3 years.You cannot confer any immigration benefits upon her until your petition on her behalf is approved and the priority date is current (if you are a green card holder) and that process currently takes about 2-3 years.

if she leaves the US after 7 months overstay in the US, she is barred from returning for 3 years. In any event since your are LPR, the waiting time is about 2.5 years so you can file I-130 after you marry her and then just wait for the time to come. If she chooses not to leave the US, then you will have to become a US citizen in order for her to eventually adjust status to LPR. That will be for sure 5 years later.

She will be barred for three years for overstaying. If you marry her, you can petition her.

If your girlfriend overstayed her visa and was out of status for more than six months, she will be subject to the three-year bar of reentry. I would advise you to speak with an immigration attorney in your area to determine what your options are.

There are several issues surrounding this case. Departing from the U.S. after having been unlawfully present in the U.S. for over 180 days will trigger a 3 years bar to enter the United States. If she stays unlawfully present over 1 year and departs, it will trigger the 10 years bar from the U.S. She will only trigger this upon departure and the only fix is to request a waiver for such ground of inadmissibility at the U.S. Consulate at the time of the visa processing. Due to the current retrogression for spouses of LPR's born in China, her wait can be of several years before she can apply for a visa. There is no guarantee how long it might take and you may be eligible for naturalization before she has a visa available under such preference category as a spouse of an LPR. I'm afraid there won't be any quick way to bring her back to the US as you expected. This is a complex matter which requires further and more detailed legal advice. I encourage you to hire a qualified immigration attorney with experience handling these type of cases.

If she is not barred for 3 years from returning, she can try to come again provided she still has a visa she can use again; or, she may need to apply for a new visa.

You need to have a full consult with a competent immigration attorney to fully vet her case and options. She is currently subject to a three year bar when she departs and that will be a ten year bar if she remains her for 365 days or more. Do not make any decisions on your own here.