Write a letter to all the employees/colleagues of this company introducing myself and asking for their support

Hi Everyone, I am Ajay and recently joined as Commercial Head in a reputed company. I want to write a letter to all the employees/colleagues of this company introducing myself and asking for their support. Please suggest some format of impressive letter for this.

Hi Sure Dear,
Here is format. Please find attached.

Hi Everyone,
I am Sanjiv kumar singh and recently joined as Recruitment and sales head in a reputed company. I want to write a email to Client for introducing myself and asking to work on their requirement. Please suggest some format in which i can reach client and ask for their requirements to work on.