Im getting married to a US Citizen. Can someone please help me which process is the fastest for green card. Thanks.

You've answered your own question.

I wanted guidance on the steps. I want to avoid immigration interview here rather have it at embassy in Nepal.

Than you should go back to nepal and let your husband/wife do the paperwork.
Wait time is anything between 6 months to year. Depending upon the number of applicants and its processing time.
If not both of you can stay here , do concurent filing, apply EAD and wait for your interview .
Choice is yours.

Thank you for your reply. I heard one can have a green card interview in Nepal rather than here. Is that correct?
Actually, I am studying here in US so I was thinking marrying her/him here. The US citizen files a petition for me here. Than I go back home, marry her then come after the petition has been approved. As I am studying here, I do not want to leave everything and wait back home for a longer time.
Any recommendation is appreciated. Thanks

कस्तो बुझ्ने गारो गरि प्रस्न सोधेको हो ? जता गए पनि लोटरी लागि हालेछ नि . किन साझा मा फुक्दै हिड्नु पर्यो ?

Mero Lottery lagyo bhanera suchana diyeko ho?

u r already in usa ...u r getting married to a citizencp holder.. u guys are together ... just get married continue living there and get ur study moving n sidewise u kan also do the processing ...i dont see any problem in your case as u r getting to live with ur partner plus complete ur study plus do ur processing from there :) so u dont have problem my friend ... stay happie :)

अमेरिकामा बिहे हुनु भनेको DV परे जस्तै हो | फुकेको हैन खुसि भएको अनि थप प्रश्न हरु भएकाले सोधिएको मात्र हो | प्रचार प्रसार हैन होला ?