Hello,

Hope you are good! I have presented a model which contains blood vessel, red blood cell and virus-cell. I haven't applied the modifiers so you can extend the model for your various purposes and I have described the modifiers purpose in the blender text editor kindly have a look into it. If you want the blood vessel to be curved, I have already set the NURBS path, so you can just play with the NURBS path to get a curved blood vessel.

If you like the displacement of the blood vessel and in case you need a curved blood vessel for your project, contact me I'll model the blood vessel as you expected and furthermore if needed it can be animated with the flow of red blood and virus cells.

Stay Safe!Good Luck!