Using prebuilds
Prebuilds are more convenient way of using monero_c in your code (although these builds should NOT be used in production). There are several ways in which you can use prebuilds
The monero_c way
Go to https://github.com/MrCyjaneK/monero_c/releases
Click on the release that you are interested in
Download release-bundle.zip
Unzip it in monero_c directory
That zip file contains all builds that monero_c supports prepared in the exactly same way as you would prepare them if building on your own. This is the easiest way to get started.
The monero_c way (different)
Alternatively you can go to releases tab and grab whatever you need, there are over 40 libraries. Surely one will fit your use case.
The build_moneroc.sh way
This method is used by xmruw and monero-tui.
It supports both building and downloading prebuilds and putting them in correct location, have a look at the code yourself
The cake wallet way
There is a simple script in cake_wallet written in dart
that runs on all platform (including windows) which downloads all required libraries for selected platforms in one go. You can take look at it here