Hi,
It is better late than never. The first thing you need to do is believe in yourself. Next, analyze the syllabus, exam pattern of SBI PO. You only will be able to know whether you will be able to crack the exam or not. You can find the preparation tips for cracking SBI PO in the below link
https://competition.careers360.com/articles/sbi-po-preparation-tips
I hope it helps.
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