How do I read to retopologize this mesh easily...ill be doing a lot of these

I would like this mesh which is now in the current shape that I would like it to be in with the correct texture applied so(but only in edit mode) to have perfect low poly quads so I could extrude the faces and model it into an animatable bear model…below is mesh

What I tried so far is … I tried to add subdivision surface but blender just shuts down I guess because of the amount of edges present. I tried to add decimate and that did reduce the number of edges and then I tried to add subdivision but blender shut down. I tried to remesh it but I couldn’t apply the remesh and then add a texture I don’t know why it couldn’t apply the remesh. I added the blender file below and in that file the selected file when you open it up is the one that I’ve already gotten into the perfect shape but the other files with the same name are what it looks like before so you could look at that too I got in the perfect shape just how I like it so I could start to model it and I did it easily with the new process I’m trying to invent but it has way too many subdivisions to
model right

https://hidrive.ionos.com/lnk/0NCmHTYM

Why do you have to use this double curve ??? I would use the outer curve, set some extrusion in (Curve) Object properties and fill to both side (maybe also some bevel), convert to mesh (maybe lower the resolution in Shape Resolution…), (merge by distance if bevel was choosen in curve setting) ring select the border, inverts selection, new face from faces (F), inset one or two times, select the inner n-gon, triangluate… if not beveled in curve bevel edge now… quads not need in inner shape because it’s a plane shape…