Here are the structures as of Version 1.0.1, some structures will have changes in values and possibly blocks. 

This is the Large Rock, it can spawn in the following biomes: Taiga, Savanna, and the Plains

This is the Small Rock, it can spawn in the following biomes: Flower Forest, Forest, Jungle, Mooshroom Island, Savanna, Taiga, Swamp, Plains and Beach

This is a Campsite, is can spawn in the following biomes: Flower Forest, Forest and Plains

This is the Mythical Birch Tree, it can spawn in the following biomes: Flower Forest, Forest

This is the Medium Rock, it can be found in the following biomes: Beach, Flower Forest, Plains, Foret, Savanna, Taiga

This is the Beach Tree/Palm tree, it can spawn in the following biomes: Beach

This is the Large Bone Pile, it can be found in the following biomes: Desert, Swamp

This is a Small Spruce House, it can be found in the following biomes: Taiga, Extreme Hills

This a a dungeon located underground, you can find good loot in the chests along with the ability to make your own mob farm with the Mob Spawners!

This is the Oak Pillager Base, It can spawn in the following biomes: Forest, Flower Forest, Extreme Hills, Plains, Beach.

This is small house that can only be found exclusive to the Taiga. It had a few blocks that can be useful through gameplay.

This is a Calcite Spike, if you mine inside there may be a prize! This spike can spawn in the following biomes: Extreme Hills

This is a Bone Structure of some old creature that used to live, there will be multiple variants of theese bones in the future, theese bones can spawn in theese biomes: Dessert, Beach, Ice Plains, Swamp.

This is a little starter base that if you complete, can be used as a good starter base for players who want to survive the night. The Biomes this structure can spawn in are the: Flower Forest, Forest.

This is a simple log structure that can help you get wood, kind of like foliage. This Log Stack up as I call it. It can spawn in the following biomes: Forest, Flower Forest.

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Ill quickly add an an image icon next update, sorry about that. (Again I need a bit of time, I finnally got everything working)

Here are the credits to the Structure Spawner I used or Frg V2

https://youtube.com/machinebuilder
https://machine-builder.itch.io/frg-v2

Please subscribe to my friend here, a bad upload schedule but makes quality content he has good videos coming soon ✅

https://youtube.com/channel/UC0tSMWNJeMQsNT1E76Rce4w

MrBobMC (in game username) helped with making a few of the structures introduced