Yea, smoking is really dangerous. Because medically chronic smoking will cause a change in the protective epithelial lining of the lung from the simple cubiodal to stratifified squamous thereby predisposing the lungs to squamous cell carcinoma.

The popular cancer of the lung in later life

yes

It causes liver and kidney failure 

Black lips. It can lead to depression. It can makes one to start developing psychological and mental problems 

No it doesn't

Its depends on how to you use...if its been abuse then that's dangerous..

So far so good

Weed is medicinal

Yes because smoking is unhealthy, it's like a slow death. 

Just use a vaporizer instead, it's much healthier. And they are not that expensive considering you never have to buy lighters, rolling papers, tobacco again.

I use this one and it works great: https://amzn.to/2Kdn5h4