How to know if this token is real? And do different networks have different market cap of the same token?

Context:

Totally new to using metamask on crypto. Was going to use one of the DEX like Uniswap, Sushiswap, et. but learn meta mask already has built in swap finder (or something, it looks like scanning for swaps?) feature for Ethereum and Binance network. ETH net's gas fees too damn high so using BNB net. Comes up with this BscScanner help verify is this the right token?

Trying to buy FTM but worried if this is a fake FTM as I heard people do scams like that. After comparing the FTM market cap on different websites, it seems different on BSCSCAN. Why is that?:

  • https://bscscan.com/token/0xad29abb318791d579433d831ed122afeaf29dcfe
  • https://etherscan.io/token/0x4e15361fd6b4bb609fa63c81a2be19d873717870
  • https://coinmarketcap.com/currencies/fantom/

ALSO am I doing the right thing using the swap built in metamask? Noob and worried might mess up.

ALSO how to tell if a coin is a scam. Any way to check authenticity (because scams minting coins with very similar names)?

How to know if this token is real? And do different networks have different market cap of the same token?