Hey Sakshi, Admissions in UnderGraduate Courses like B.Sc are given on the basis of an entrance test called Under Graduate Admission Test (UGAT).
The application for admission test will be available from the Second week of April 2019 while the last date of submission via both Online and Offline modes is in the First week of May 2019.
Hope this helps.
You can check out more details about this exam and admission forms by referring to the link below:
https://university.careers360.com/articles/allahabad-university-application-form
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