Is the Ethereum going to take Bitcoin's place because of the incomming fork ?

Bitcoin's network is saturated.

A fork is needed for bitcoin to survive as a currency.
A soft fork is a minor adjustment to the code. The user can continue to use the program without complications for a short period. A hard fork requires an update to continue to use the program.

Why A Fork?

A fork is needed for bitcoin to address the need to scale the network. As more users join the network, transaction speed slows, creating various problems.

A soft fork modifies the code without splitting it. A hard fork splits the code. Either a soft or hard fork will likely cause bitcoin to lose value.
An hard fork will probably create 2 different currencies like it happend with Ethereum and Ethereum Classic.

Many staffers favor a soft fork called SegWit that will not split the code. The staffers who don’t favor SegWit want a hard fork that will significantly increase the block size. To note that the second option is the worst for the miners.

Bitcoin needs to increase its transactions speed. If bitcoin cannot overcome this issue, it may not survive as a digital currency.

No one can be sure of what will happen, there is only one way to be sure to keep your money :
You may choose to sell your holdings before the fork, evading the risk that bitcoin’s value falls significantly.

Hence, a fork, hard or soft, is inevitable.

I think that ethereum, the main competitor of the bitcoin will see its value taking off :

The fork will make bitcoin's value fall and bitcoin's holders will look for ethereum.
And an hard fork could separate BTC into two Altcoins and thus divide its market capitalisation.

Ethereum will therefore become the biggest market cap making a lot of noise in the media which will bring new investors and here we are in a virtuous circle which will bring Ethereum's price to the moon.

Good luck.