Use a Grid Panel :
This will add a label and a text box on the same line (extracted from a project and modified for simplicity) :
lbl = Label(text="My Label")
self.grid_panel_1.add_component(lbl, col_xs=0, width_xs=6)
tb = TextBox(text="My Text Box")
self.grid_panel_1.add_component(tb, col_xs=6, width_xs=6)
It’s the only way I know how to do it, and it’s the recommended way :