A 10g tank will be much much better than a 5g. Still really small and a bit more work than say a 20g tank. You could get 2 tiny fish, preferably gobies or blennies as they dont swim much.
Corals will be attached to ceramic plugs, called frags. You can get some corals with a skeleton, like brain corals that stay put at the bottom of the tank, on the sand due to their weight. Others can be removed from their frag plugs and glued to rockwork.
Look at LPS
corals, like hammers and torches, they sway just like an anemone and are ALOT easier to keep. People always mistook my lps
for anemones, they can look very similar. Alot will depend on the lighting too, as LPS
corals will need more light than say mushrooms and zooanthids.