I have a 300 feet deep bore well. Water is to be stored at 3rd floor level above ground. Which type and capacity of pump would you suggest for use?

Don't think a jet pump will work that deep. Capacity depends on what volume of water you will need. We can't determine that with the info you gave.

I agree with Brian, don't think a jet pump will work. There are shallow well jet pumps and deep well jet pumps. Without doing any research, I think the limit of a deep well jet pump is 120 feet.