Data issue for forecast daily sales



I have less than 1 year data, When i forecast next 7 days sells and match actual sell then difference between forecast sell and actual sell is very high.
I used prophet package in R.
So my question is for forecasting next 7 days sells data is enough or not???


Although it is true that data is not enough but we can still use it to predict approximate sales for the next 7 days. You can read more about forecasting from these links.
Link1 -
Link2 -


Can you tell me how i improve forecast efficiency ??


Do you mean forecast accuracy ?
If yes then you can try tuning the parameters of the model and compare the RMSE on your test set.