After the walls chapter 1

In the year 870 the titan threat was all but defeated. The survey corpse had returned as heroes and humanity rejoiced. however the remaining titans adapted. They became smarter, faster, stronger and most importantly... self aware..
This new titan threat destroyed the walls we hid behind and almost overnight destroyed humanity.
10 years later the lone survivor of the survey corpse main squad Miles Vogel wakes from a coma. He finds himself alone in the woods. His mind is lost in the days of the walls. Until he is saved by a girl with jet black hair.
Where is the survey corpse?
How do the last humans survive?
Where did the titans take Eren. and why.
Read on to find out