I will not recommend to use Bitpay. First thing there fee is quite higher from others and they will make trouble with KYC requirement. If you know some technical work then you might use BTCPay as already explained above by other users including different between BTCPay and Bitpay.

Also you may use Electrum merchant for more safety, but I am not sure if there is fee requirement for receive fund, if so then obviously will be lower than Bitpay. You may read their article, How to accept Bitcoin on a website using Electrum

If you don't have enough technical skill then you may use third party API like coinbase (But is not recommended). As far as I knew they doesn't required deposit fees. You may read more about their commerce API, https://commerce.coinbase.com/docs/

If you in case use coinbase API then you should move your fund on Hot or Cold wallet regularly due to security reason.