Hello, first post here..

I have a 2019 C300 and need some help.

Last few days was smelling coolant, today while driving home car got hot and check coolant level light came on. Once I got it stopped I opened the hood and found that coolant leaked heavily from under the intake manifold.
So I searched online and found its a common issue with the coolant pipe. I did a search on here before posting, and was not able to find anything about replacing this myself. I am certain I can do the work myself, I just had a few questions about the work to be done.

1. Are the intake manifold bolts re-usable?
2. I had a hard time finding an intake manifold gasket, so I just ordered the one that showed up searching on autohauz.
3. Is there anything I should know about removing and replacing the pipe assembly and hoses?
4. Where can I find torque specs to retighten the intake manifold?
5. Is there a procedure to refilling the car with all new coolant? Other vehicles I have worked on you needed to pour the coolant directly into the crossover tube and not the reservoir.

If anyone could help me out with any info I would really appreciate it..

Thanks for your time.