Hi everyone, myselfI am Rithika.

You could either say "I am Rithika." or "My name is Rithika."

I'm pursuing betech 1 year in IT branch in one of the top colleges in Hyderabad city. I completed my intermediate in Viitjee doctors academy located in Madhapur. My schooling is done in Warangal in a government high school. I will be always grateful to the Hmheadmaster of our school and my mother.w With theire support, I'm currently studying in a well known college .

Leave a space between the end of a sentence and the beginning of a new one.

When you say "Hm of our school", I assume you meant headmaster? If I'm wrong, ignore this.

The pronoun "their" is used when referring to multiple people in a possessive sense, e.g. "This book belongs to Andrew and Claire. It is their book."

Hi everyone, myselfI am Rithika.

I'm pursuing beiotech 1and I am in the 1st year in the IT branch in one of the top college in Hyderabad city. I completed my intermediate in Viitjee doctors academy located in Madhapur. My schooling iwas done in Warangal in a government high school. I will be always be grateful to the HmM of our school and my mother.w With theire support I'm currently studying in a well known college .