Gas fees are a fundamental requirement for any transactions, swaps, or activities on a blockchain. These fees go directly to validators on the blockchain, and not 1inch Network. For more info, see this article.
Native assets can be purchased in several different ways:
You can click "Buy ETH" located at the top of the 1inch desktop site. This will take you to a 3rd party payment processor, MoonPay, where you can purchase ETH with a credit/debit card.
***Please note: ETH is the only asset available for purchase through MoonPay.
Alternatively, you can access MoonPay to buy assets by clicking your connected wallet address in the upper right hand corner, and clicking the "buy" button within the following account window:
If you already have a little bit of ETH, you can swap for more right here on 1inch.
Layer 2 ETH, Aurora ETH, BNB, MATIC, AVAX, FTM, xDAI, and KLAY can also be purchased on any major centralized exchange, like Coinbase, or Binance, or can also be swapped directly on 1inch.