When the network hits a certain block number, the mining reward — the bitcoin amount miners earn for verifying transactions — is halved.
To be pedantic, it's the block
subsidy that's getting halved. The block reward can be anything, as long as there are mined transactions which pay respectively.
So, I think when the halving in April occurs, the price of BTC will improve and reach to a height where it will be making them the same or more money even from the fee which from another point of view
This is not how it works. Just because the mining reward will shrink, it doesn't ensure price increase. If the miners can't pay their bills, they simply shut down their business. Block reward shrinking means pretty much hash rate decline on the long term.