So, Here i am going to wrote about the companies that hire all tier colleges students through off-campus.
You can apply in goldman sachs through their carrer portal website, they always open their application in the month of july or august, the same application is for both Interns and for freshers, after applying you will receive the test link later. Another way to get referrals ,if you manage referral its fine.
You can always visit microsoft career portal to check the the oppurtunities, Mainly for interns the application is open in the month of june,july,august or you can check on their career portal website they provide the month when they will open the application. Another way is through referral if you know someone you can ask for the referral. Microsoft also organises many program like microsoft virtual experience program, and they mention there those who has experience these microsoft program will increase your resume weightage, so you can try it too.
Amazon hire throughout the year. You can always apply from their carrer portal but make sure to apply in time, they open their application mainly in the month of april/may/june. So apply as soon as possible after application is open. Another way is through referal , if you know someone you can ask for referal. Now, amazon also take off-campus application through their different program like amazonWOW , amazoWit (Only for womens). Conversion rate in amazon from internship to full time is really high.
You can get in google by participating in its contests like kick start, if you will get rank around 100-200 , you may get an interview call from google, and you also apply through their carrer portal website. The best way is to go through referals in google if you can manage to get it.
CodeNation organises three contest per year, one contest is reserved for tier-1 people and other two contest are for everyone , the other two contest are the addition of codeAgon which comes around in the month of september and january, if you want to visit test they usualy post on facebook page, if you get rank around 100 or 200, you may get an interview call from codeNation, the other way is to connect with employee of codenation and get a referal.
In case of D.E shaw you can apply on their carrer portal page, if you are fresher better to apply after feburary , If you apply noramlly through their portal there is 90% chance you will get the test link. And also if you can manage referal then it also fine.
zeta and Sharechat
In these comapnies you can look for the internship which usually open their application in the month of november,decemeber, the conversion in both of these companies is from internship to full time job is very high, and the other way you can go through referals.
Postman , cure.fit
They usually hire after doing 6 months internship, so the application is open usually in month of october, november (months you should keep checking by yourself companies may vary their hiring process). The chances of converting from internships to full time is very high in these companies, another way is to get referrals.
NOTE:- Application opening months of companies may vary so you can keep visiting their career portal page.