Procedural Splines generated from other Procedural Splines

Hello, i want to create an entire city with PCG (and potentially PCGEx but we’ll let that aside for now) and my issue is that i want first to create Roads. I would like a main road (done already), then multiple roads starting from the main one, and finally other shorter little roads starting on the branches made.

I currently got the result i wanted for my main road, now is the part where i can’t manage to generate new individual splines starting from points on the first spline.. and it’s been a struggle for the past days hahaaaa.

Any idea of how i could do ?

My first screenshot is how i generate my first main road, and just below i tried to generate a new spline but meh it isn’t working.
The Paint screenshot is what i would like to achieve in 3 steps.

Thank you guys