Can somebody help me with the lightning inside the jellyfish like the one in the picture

hi maybe i can help! just to clearify two things, what is the tentackles made of? curves hair etc? they look a little straight, put some fallof to them, and what render do you use? most of the light in a scene like this would be from above, and a little bounce light from the atmosphere in the ocean, you could try to add a area light above and add volume scatter to your world settings, what does the shader of the yellyfish look like? not the tentackles,

They’re hair particles and I just want to know how to do the inside lightning not the whole thing and thanks.

I think the body of the jellyfish should have some translucency, a bit of SSS and and diffuse component with mild roughness.
The tentacles should emit a little light and maybe get some SSS too.

Lighting of the scene should be one, two or three points with in priority upper center (lighting slightly from above), then maybe lower right and lower left (lighting slightly from below).

For the environment you could use a particle system for these floating elements, some DOF (not too strong) and maybe a little volume scatter.

Just a hair material with a light inside in cycles works fine for me:

And if you want the tentacles a little more visible you could mix an emission node in:

Good luck, please show your result. I like jellyfisch :wink:

Here’s another test :

Well here’s where I went so far

The last two are a huge improvement. The secone last one looks best to me because of the more natural floaty appearance of the tenticles. On the last image the tenticles seem to behave too uniformly.

Nice improvement.
I still think you should add a little emission to your tentacles shader.