Q: all that remains of it とはどういう意味ですか?
A: "all that remains" in this sentence means "the photo album is the only thing left" (maybe the extended family is dead but the photo album is still there)


Q: fossil remains. と fossil remainders はどう違いますか?
A: I have never heard some say or write “fossil remainders,” however, it is correct English. They mean the same thing.


Q: I also might make a discover that remains in history 😏 この表現は自然ですか?
A: I also might make a discovery that remains in history 😏
Q: I love you with all that remains of my rotten heart この表現は自然ですか?
Q: I am excited to be able to see many remains which are seen in textbooks. この表現は自然ですか?
A: Typically, the word "remains" is used when talking about corpses or broken items.
Q: All that remains for me to do is waiting この表現は自然ですか?
A: Corrections:

All that remains for me to do is wait.

espera = wait
esperando = waiting