itch.io

whenever you click the download button it will give you an option to pay as well as download, if you  look above the 2$ you will see in grey text "just take me to the download" its optional to pay when the game is free, it just supports the creator

in all reality the ones you have to be worried about are the games that force you to pay to play, only accept card and are cheap, again it is the internet so do be sure to read comments because there is 100% malware that you can download, but for the most part just be sure to read and you will be fine