How Do আপনি Make Tribute Videos?

I have seen pretty amazing tribute চলচ্ছবি for TPoM on ইউটিউব and I have been wanting to make them myself. The only problem is I don't know how to get the চলচ্ছবি from the episodes and I also would like to know the best softwares (or whatever they are called) to make the চলচ্ছবি on. If আপনি could help then that would be great, thanks! :)