Unable to Swap BASE for ETH

Can someone PLS provide simple instructions on how to do swap my BASE for ETH? I swapped ETH for BASE on SuperBridge to buy a coin on a DEX. Now, I want to swap it back to ETH. I've used a dozen different bridges tonight + tried swapping BASE for ETH in my Coinbase Wallet to no avail. I even bought $50 worth of ETH and transferred it to my Coinbase Wallet. Yet, I still can't get ANY bridge to complete the transaction. I just read about using a L2 or roll-up to swap BASE for ETH off-chain, but I have no idea how to do that! Can someone provide clear, mechanical instructions on what to do? Thx!