Line plot with multiples variables y

I am trying to create a line graph with múltiple y (i have like 800 variables) vs date. I am trying to put efficiently all the variables in in y but i nothing work. in the other hand, i want that all the variable start desactivated so i can choose what variables activate later, but i dont know how to do that.

fig = px.line(dff, x=‘datetime’, y = df.columns.unique())

i tried this (and many other ways) for select all the variables.