I'm curious as to what sets Bitcoin apart from these other coins. Considering that it's been said that Bitcoin won't be impacted and will continue to grow, what are the key difference between the two Bitcoin and other coins?
you always have bitcoin on one side and all other altcoins on the other. only bitcoin is completely decentralized while the others (like FTX and Luna) are centralized and controlled by certain companies or people. bad management can lead to a complete collapse, which was seen in obvious examples.
The second is about Bitcoin mining; what is the difference between investing in bitcoin and mining bitcoin, or are they interchangeable?
For mining, you need an initial investment in hardware, for mining you need an initial investment in hardware, which will later bring profit (in Bitcoin) when working. investing by buying bitcoin is really just a fiat-to-digital asset conversion and in that way, you will save value with the possibility of growth as the best scenario.
from your question, it seems to me that you are confused that you are getting offers to invest in online mining platforms. I hope you haven't already invested some money in it because these are always and exclusively always fraud schemes. bitcoin mining is done exclusively with hardware and all platforms that offer you such a service online with a high percentage of earnings are scams.