Which is the simplest way to scroll a text sting across the screen?
I mean plain 2d text
translate the texcoords or positions over time?
Something like text.x -= amount * time;
draw it on a texture, then move a texture quad with it.
If the text is too long, split it to multiple textures (one tex per word, or even per character).
Are you able to display a string on the screen that isn’t moving?
That’s the first step. If you can do that, making it move will be easy.
assume that you render your text already somewhere at x,y. now rendering it with say x+2,y+2 will put it into different position. doing this over time each frame adding some displacement will look like the text is moving.