I have a few questions:
1. MAIN. When will be accessed deposit and withdraw for biggest exchanges? Like Bittrex, Binance, Bitfinex?
2. So main difference of ETH is that you can stake and set up MN, is it correct?
3. When WP?

Waiting for answers.

joined to the airdrop

If you lose you private key and wallet.dat file access to your address will be lost forever. This is fairly for every cryptocurrency.

There are 2 steps which you can do:
1. Recover erased data.
2. Check again if your wallet has been deleted. Go to:
   For Windows: C:\users\userName\Appdata\roaming\SEND
   For Mac: $HOME/Library/Application Support/SEND

If you see this folder then you need to save wallet.dat file. It could be your wallet. And then you need to delete this folder and reinstall wallet. But I am not sure what are you did in there, so these actions could make only worse. You can go to Discord chat - #help channel and ask there. (https://discord.gg/yrm5EZB)

Bitcoin had cost $0.01

If your staking is active you need just to wait. If not try to restart the wallet and unlock it. Status should change to green "staking active" (there are 4 indicators in right bottom corner, you need second). The first Staking reward can take several hours or days.

Probably you not correctly installed wallet. Make backup your wallet and try to use this video instruction - https://youtu.be/CVsjp2lpc7I


You will get 50% coins every year. 6250 / 2 = 3125 per year / 365 days = 8.5 per day. And you don't need to pay for VPS. I think for now it is better that MN. But in future MN will be get more coins than staking.

Btw you can check also this reward table https://docs.google.com/spreadsheets/d/e/2PACX-1vTB2dKDCc8rsotlbDGe7wKL3JLqZR9nWkqWJgmyGp_PJv7lUxMqWr9luJIbL1TSCzxqIKlkxpVsLt1C/pubhtml


Amazing community in the Discord chat) Btw if you have problems better to use Discord - https://discord.gg/xJthHER