Optimize & Animate 3D Models for Mobile Game

I have 3 existing 3D mesh assets for a dark fantasy Drow / Underdark mobile strategy game. I am learning Unity, so I need the final files to be beginner-friendly, clean, and easy to import. I am not a professional programmer.

The assets need two things done:

Mobile optimisation – the files are currently too large for a mobile game. Please reduce polygon count, file size, texture sizes and materials while keeping them looking good from an isometric/top-down Unity mobile camera.
Add life/animation – I want the buildings/environments to feel active, like real work is happening, not just static models.

The 3 assets are:

Mushroom Farm – add simple animations such as slaves/workers picking mushrooms, mushrooms glowing/pulsing, spores, mist, or small ambient movement.

Zurkhwood Forest / Timber Area – add slaves/workers cutting timber, carrying logs, subtle tree/fungus movement, dust/spores, and glowing Underdark effects.

Drow Throne Room – this is the most important building in the game and should look impressive. Add purple magical lighting, flickering crystals/flames, moving webs/silk, guards/servants idle animations, mist, particles, or other dramatic effects.

The style should be premium dark fantasy: Drow, obsidian stone, glowing purple magic, bioluminescent mushrooms, spider/web motifs, serious and not cartoonish.

You can use artistic licence to improve the look, provided it still suits a Drow mobile strategy game.

Please provide Unity-ready FBX files or Unity prefabs, textures, named animation clips, and clear import instructions. Please also advise final file size, polygon count, materials and texture sizes.