Nice rote throgh the Cederberg Mountains. A beautiful dirt road, not too remote and good accommodation options. In the summer it can get very hot in those steep climbs.
The Cederberg are actually the home of the Rooibos tea. Word wide only here the red bush is grown and processed to tea.
The first 61km and 3-4km before Algeria are paved. The rest is dirt road that is mostly quite good. The worst part is just before Sanddrift and from Algeria to the dam. Some climbs are really steep.
There are more than enough campsites along the route.
Buy food in Ceres or Clanwilliam. Water you can get at the accommodation options and is no problem.