questions dealing with the F-Droid open-source "app market" or its app. Note that questions related to publishing or otherwise interacting with F-Droid in a development capacity are off-topic.
F-Droid is an alternative „App-Store“. As with google-play-store, you can browse apps and install them unto your device. It has a website you can visit with your browser – and a client app for your Android device, taking care for installing and updating your apps. But other than with Google Play Store you don't need an account, and your privacy is respected not only by the "store" itself but also by the apps available there.
If you are interested in a detailed description, including how to install and use F-Droid, you could e.g. take a look at the article F-Droid: The privacy-friendly alternative to Google Play Store by Izzy¹.
¹ Disclosure: I (Izzy) inserted this link here on request. It goes to my site.
