How To Congratule New Baby How To Write Memo To My Proffesor Explaining My Absence Form Classes For Next Week Because Of An Operation?

How to write memo to my proffesor explaining my absence form classes for next week because of an operation? - how to congratule new baby

Please help me! I do not know how to write an official letter, and I have a note to my teacher that I am writing away from classes because I have next week Opperations.