Form a view that's about death, mostly (6)
I believe the answer is:
ideate
'form a view' is the definition.
'that's about death mostly' is the wordplay.
'that's' becomes 'ie'.
'about' indicates putting letters inside.
'mostly' means to remove the last letter.
'death' with its final letter removed is 'deat'.
'ie' enclosing 'deat' is 'IDEATE'.
(Other definitions for ideate that I've seen before include "Fancy" , "Imagine (psychology), aid tee (anag.)" , "Form in the imagination" , "Form a picture of" .)