Personally I use the following bridges:
Mostly I use this one as it supports a lot of chains and has a small minimum for transfering:
https://bridge.evodefi.com/ (BSC, Polygon, Fantom, Heco, ETH, Avalanche, Arbitrum, Solana, Tron)
Two more bridges are:
https://www.binance.org/en/bridge (ETH, Tron, BSC), because it is convenient to use bridge just on exchange.
https://www.xpollinate.io/ (ETH, BSC, xDai, Polygon, Fantom, Arbitrum One, Avalanche)
I am not so familiar with how the bridge works - I know the meaning of a bridge because I am using it for daily commute but not so knowledgeable on how the thing can work in cryptocurrency. So am gonna adopt it to my scenario: I have an ERC-20 token in my MEW wallet...can i sent it to a bridge and will not MEW charge me still high transfer fee? This has been my problem actually I could not transfer the said token and make it into money because of the high Ethereum fees.