Graduation is the basic requirement for Banking Exams like SBI PO or IBPS PO. Hence after 12th, you must first complete your Graduation, followed by preparation for PO Exams.
For more information about SBI PO do follow the link below
https://competition.careers360.com/exams/sbi-po
For more information about IBPS PO do follow the link below
https://competition.careers360.com/articles/ibps-po
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