Ans, 2: Mining altcoin require low cost? Isn't it the same with bitcoin? I no sabi if the two get difference, if altcoin mining materials dey low, then we move to altcoin but the problem be say, we go fit make profit from mining altcoin?
You are right, to mine bitcoin, graphics cards like Nvedia and AMD that can be connected in grid to make up mining rig for bitcoin mining are no more profitable to mine bitcoin, but still possible to mine some altcoins, I am not sure about the strong altcoins like ethereum, litecoin and others in such high categories. For bitcoin mining, ASIC like Bitmain antminer S19 will be needed or any other good new ASIC like the Antimer T17 which is also efficient.
At the end of the day, regardless of what you're mining or whatever equipment you're using, having adequate or constant electricity will play a huge role in ensuring that you remain a profitable miner and constant electricity is something you only see if a few select places in the country. It's also worth considering the amount of power bills that would be incurred in the course of the mining operation. Talking about what to mine, I'm also of the opinion that mining bitcoin now might not be a really good idea especially for an individual miner. smaller altcoins with more rewards and some minor difficulty should do just fine but new projects often focus on POS staking instead of good ol' mining like in the early days.