hello aspirant,

YES you can shoe the UP Board Class 12th Marksheet next year for JEE Mains exam if you have shown the CBSE Board class 12th marksheet.

But remember that every candidates are allowed to give JEE Mains for 3 consecutive times only and JEE advance for 2 consecutive times from the year of passing the class 12th examination.

further, to know more about the JEE mains examination, you can follow the below mentioned link to know more about it  in detail : https://medicine.careers360.com/articles/neet-eligibility-criteria

I hope that this will help.