It is a common query from the non-native English speakers, who want to know how to speak about an activity in future.
Like the future course of action of some other person or an activity which they are sure of completing by next week, month or day. If you are sure that you will finish a book which you are reading by month-end, you can say it like:
I will have finished reading this book by month end.
Some other examples:
My tests will have finished by September 15th. So we can plan this journey after that.
I will have revised my entire course twice by then.
Here we gave you a few examples of future activity. Grammatically you call it Future Perfect Tense. But there is no need to remember tenses and their names, just learn how to spell out your thoughts about future, with the help of these examples.
The lorry will have left.
He is a stingy guy. He will have saved 100 dollars by the end of this semester.
Now if you think that you would be continuing with that activity (not finished by that time in future) then it's equally easy:
This time next Monday I will be repairing this cycle.
In July I will have been studying in this institute for three years.