Hi Namdev,

EAMCET is a state level entrance exam conducted by JNTUK on the behalf of APSCHE, offering admissions into various UG courses offered by public and private colleges in AP. It is conducted only once a year. The main eligibility criteria are,

• There is a minimum age limit of 17 and the upper age limit is 22 for general and 25 for SC/ST. 
• You should've cleared your intermediate final year physics, chemistry and biology with a minimum of 50%.
• There are no restrictions as to how many times you can appear for EAMCET as long as you don't cross the upper age limit.

As there are no restrictions in the number of attempts you can give for EAMCET as long as you fit in the age criteria. 

I hope this answer helps you.