I'm not sure what you're talking about... Film can never be exposed to light, not even for a split second until you are done developing it.

So, if you are asking whether you can open the cartridge and begin to load it, no. You will spoil the film.
If you are asking whether you can use a leader retriever tool to pull the head of the film out of the cartridge, feed it onto the reel then put it into the changing bag and pop the cartridge open, yes you can do that but it's a whole lot of fussing for little payoff.

Best Solution:

Get a piece of film to practice with. It can be a piece that you have already developed or a piece that you accidentally spoiled. You could even sacrifice a roll of film in the name of science. It doesn't matter.

Take your practice film and practice loading your film right there in the daylight. Do it several times until you can do it with your eyes shut. From that point you should be able to do it in the darkroom or in your changing bag without problem.

Fussing around with retrieving leaders and half-threading film isn't productive and you're just flirting with disaster.