Making a discord-like message system, is it possible?

I'm trying to figure out how i can make something like this, but i'm really not there yet.

What i need to do is to make it so text messages defile from bottom to the top, and when it reach a certain high, create a scrollbar that dynamically change depending on the amounts of messages sent.

The thing is, it also must store every discussion, every message, and be accessible at any time by the player. So the text must stay, and every line must be displayed forever after their first appereance.

I can make the messages go up and yaddi yadda using variable and storing positions in them, but i have 0 idea for the dynamic scrollbar and how to make it so when the scrollbar go up, the messages previously sent are displayed again (without making the scene 50km long. I'm searching for a solution that'll let me make reappear previously sent messages in a 1920*1080 scene when using the scrollbar. That must mean erasing text when they're outside the game zone and making them reappear when the scrollbar goes up or down, i think?)

If you have an idea on how that would work, please let me know. Thanks a lot !

I'm not too sure on how to do the scroll bar, but i think there is a tutorial on that by Lessis Games on youtube. As for saving the messages, you could try saving each message in order in a 1-d array that grows as more messages are stored, than save that using localstorage or whatever other method.