Hey there! Sorry about the delay. You'll want to check the RenPy documentation for how transforms work.
https://www.renpy.org/doc/html/transforms.html
RenPy has a few built in ones, like 'at right' or 'at left', etc. The pack here gives you more of those prebaked options with the ability to tweak their y and x positions in the configuration.
In one of their examples:
show eileen happy at right
In short, you can add 'at scene_back_left_far' to the end of a line where you show a sprite and it'll move them there.
It would then look like this:
show eileen happy at scene_back_left_far
Hope that helps!