I whent into a minecraft world and looked at the items and some of the tabs where empty, blocks where gliched and there wasn't any vehcles or guns

Sounds like you didn't install any content packs. https://github.com/FlansMods/FlansMod/wiki/Installing-FlansMod

Closing for not following the issue reporting guidelines: https://github.com/FlansMods/FlansMod/wiki/Issue-Reporting