The tooltip of any Journal Page or Note can be read by you as a player by moving your cursor over its icon in your inventory - and then it can only be stored away.
Torn Journal Pages and rarely also Scrawled Journal Pages as well as other possible Notes can be found in the game in all kinds of randomly spawning Treasure Chests.
Sometimes also Things or Keepas of any kind might provide you with them.
The sole purpose of Journal Pages and Notes is to give you hints about the background-story of Creativerse.
These notes seem to be related to the Data Chips that can also be obtained from Treasure Chests, Things and Keepas).
The Journal Pages mention an unknown female entity named Pixi who seems to have written the Data Chips and who seems to have been created by the male scientist from Earth who seemingly has written the Journal Pages and other Notes.
The "order" in which these Journal Pages and Notes had been written is unknown and you will have to do with guesses; however it is not necessary to put them into a particular order. They are not parts of an ongoing story nor coherent information, just snippets of vague hints about the gameworld and background that won't fit together clearly.
There is no "reading device" in Creativerse where you could insert them or anything like that.
Journal Pages cannot be used for crafting, cannot be put into any quickslot, can't be placed into the world, cannot be consumed nor "learnt", but they can be traded between players on the same gameworld. Upon obtaining a new Journal Page a message window about its discovery will be displayed.
See Note.