The question is essentially based on the ethereum currency.
How can smart contracts increase the value of coin?
first there is always an underlying hype going on which pumps and dumps the coin.
second the smart contracts are currently only being used by many ICOs and if someone wants to invest in any of them they MUST buy ETH, there is no other way for 99% of them. so a fake demand is buying a lot of ETH which causes a bubble.
Does not the currency increase with our investments in it using transactions with own currency and etc?
Ethereum is not a currency!
A company that chooses to use the blockchain platform through a smart contract with ethereum how will the procedure? I get a little confused.
i am not an expert in smart contracts and the process of ICOs to be able to explain them but if that is what you want to learn about then there are good sources online teaching how to create one.
you can also copy one of these projects out there.