Which Grade should I join as per my date of birth

The date of birth is 13.05.2014.
That means you will be completing your 9th year by the 13th of May, this year.
The admissions for 2022-23 are already over and the academic year will be ending by this month's end. So you can't join the 5th class this academic year.
Now you are in the 4th class. That means you will be in the 5th class automatically in the year 2023-24. That means you will be in the 10th class in the year, 2029-30. By that time you will be almost completing your 16th year.
The minimum age limit for admission to the 10th class is the completion of the 14th year. If you complete your 6th class in the year 2023-24 also, you will not have any problem with your 10th class examination.

In India, the typical age for students to appear in Class 10 board exams is minimum 14 years. However, the age may vary depending on individual circumstances such as academic performance and previous grade promotions. Additionally, some students may choose to take the exam at an earlier or later age due to various reasons, such as taking a gap year, repeating a grade, or accelerating their academic progress.

Determining the correct school grade based on a child's date of birth is an important part of the admission process in most Indian education boards. Schools generally follow age criteria set for each class to ensure that students are developmentally ready for the academic level. For example, a child born on 13 May 2014 would complete nine years of age in May 2023. According to common school admission rules, a student must complete the required age by 31 March of the academic year. If the birthday falls after this cutoff, the child may not be eligible for promotion or admission to the next grade in that session. This ensures that all students in a grade are close in age and maturity. Since admissions for the 2022–23 session would already be closed by March, the student would not be able to join Class 5 that year. Age eligibility helps maintain fairness and uniform learning standards in schools.