Hi new to Subeta and just got a treasure map piece what do I do with it. Do you have to find other pieces. If you could please help.

Yes, if you find all 9 pieces (or buy them from other users) you can take them to the Treasure Maps page (link is also on the Games page, in the Collection section).

There are two maps, the original and the Uncharted Land Map pieces. I don't know exactly what the regular map pieces will do (I think give you an sP reward or something, not sure if it's worth the cost of the map), but completing the Uncharted set will give you access to the Omen Islands area on the Subeta map.

The page explains a bit more. You can complete the regular treasure map multiple times, but the Uncharted one can only be completed once for access to the new land. Some of the map pieces are more expensive than others too, so if you're not interested in using them to complete the maps you could try to sell them.

Thank you for help I could not find any thing about them.

completing a regular treasure map will award you with a random amount of sP and possibly an item, but it's not much and you'd make more profit just selling the pieces. however, there is an achievement for completing the map once, and it is also one of the pre-requisites for getting into the blue building.

Thank you did not know about blue building just been reading about it