Hi @shohel44, thank you very much for taking part in this challenge!
The strokes are too hard and thick, it's important to keep this in mind if you want to colour it later. The first pencil strokes should always be fine and delicate so as not to damage the support (paper) and to be able to erase as needed.
The triangle composition is good but the three flowers are almost identical, that's good if you want to make a pattern but not for a realistic drawing. Artists often try to tell a story by including flowers at different stages of their lives.
As a consequence of too hard strokes, it is impossible to erase them completely and this is clearly visible in the finished drawing. The mistreatment of drawing paper is even more evident in your selfie.
Always try to take care of your drawing paper, it is a very important element of your artwork.