It is permissible for ordinary people to offer the Janazah prayer for one who commits suicide, but it is prescribed for the scholars and prominent figures not to offer it, as a rebuke and so as to deter others from committing suicide.

Praying to the occupant of the grave is major shirk. Praying the funeral prayer at the graveside is permissible. Praying the funeral prayer in the graveyard is permissible. Praying towards the graveyard is haram according to the correct opinion.