So I am planning on buying shares of an early startup which is doing an internal round funding and I got the opportunity to invest. This is my first time investing and would want to know what are things to consider and what I should ask the startup for before I hand in a cheque.
As people are suggesting, you should do good due diligence. This would talk a long time to answer well. Finding others who have invested before and getting perspective can be helpful. One place to start besides local startup groups is the book by David Rose called "Angel Investing"
it outlines some of the process of due diligence at an early stage Startup