How to create face in beizure tool

can anyone help me to create a face in beizure tool i have created spline in the blender but cant get faces to get modelling started. please helpimage

The first thing you would need to do is to convert that to a mesh.

Note: This is going to be a bit nasty to fill in with a face since it has so many curves and is so small…

Make sure to have an even number of vertices…Get and install Edge-Flow
So you can space edges and vertices evenly on the mesh…

Use the (included) Polybuild tool to start building the inner face from the edge mesh…

You can use the annotate tool to help you lay out where and how to add faces to fill this in…

You might want to set the curve to 2D ( Object Data Properties → Shape) and fill it (or not) and convert it to mesh ( Object → Convert → Curve )while keeping the original curve (in options).