Ahsan Allaahu ilaikum: i know from the extra prayers are rawatib, duha, qiyam al layl , before maghrib etc. But other than that can we pray nawafil and what do we intend if its before or after dhuhr or more after 8 rak'ah ruha?

Yes, beyond the well-known voluntary prayers you may pray general voluntary prayer (nafl) at any time, for all the night and day are a place for voluntary prayer, except the times of prohibition, which are after Fajr until the sun rises, after Asr until it sets, and when the sun is at its zenith just before Dhuhr. For general nafl you do not need to name a specific prayer, it is enough to intend voluntary prayer. As for Duha, its least is two rakahs and its best is eight, and if you pray more than eight, ten or twelve or more, there is no harm in it. Allah knows best.