With general request comes general response 
For export into Excel, you could use a function like openxlsx::write.xlsx() or readr::write_csv() (csv will be consumed by Excel without a problem)
For export to ppt, you could:
- Save plots with
ggplot2'sggsave()and then paste them into your ppt - Switch from an
.Rscript to a.Rmddocument and knit it as a presentation.
Feel free to explore every mentioned function by calling help on it in the console. You'll find out what arguments you need to pass and how to edit your outcome.
(for example, type ?write_csv in the console after loading the readr package)