I don't know how to really explain this problem besides that my model looks weird in every mode besides workbench and Eevee the final one is Eevee i just forgot to add text here is the file download https://mega.nz/file/m81n2aYD#MFy4hopOJopsAM_tQdplgJVLKKQSLsyi-Wfvjt4Fm8Q
The model looks weird in Eevee and Material Preview (which is similar to Eevee) because the materials have transparency enabled (Blend Mode is set to Blend) and Show Backface is enabled.
Select render engine Eevee to see the related material settings. Select a mesh part, go to the Material Settings and untick Show Backface. Repeat this for all mesh parts/materials: