I have cloned the following GitHub project to my hard drive.
https://github.com/leozide/leocad
I have also installed Qt Creator 4.5.0. However, when I try to loa
Qt is a cross platform framework, thus supporting a bunch of c++ compilers like MinGW GCC, Clang ...etc. a Kit is a set of Qt packages designed for a specific C++ compiler and implements the Qt libraries for that compiler, this is what you need to compile your project in Qt creator .. and they are not part of Qt Creator itself, they must be downloaded. below steps are suitable to get Qt fully functioning.
The Qt open source.
There are two ways to get Qt, the first is to download the source code
packages/files and build Qt yourself (but this would be needed if you have a reason to build qt packages from sources yourself). this not covered here.
Steps to install and Configure prebuild Qt Open Source.
Download Qt Online Installer for Windows, usually from this location Qt Online Installer for Windows, this is an online installer for Qt.
Run the downloaded installer, it will guide you through few steps like creating an Qt account and logging in ...
You will end up to the component selection screen and this is the most part.
Expand the Qt Selector tree, you will get 2 groups, A list of available prebuild Qt versions, And to the bottom a Tools selector tree.
make your selection of which Qt version you wish to be downloaded and installed.
Then expand the tree for that version and Choose the components of your interest, these are package kits for a list of compilers .. (For example: a windows user might choose "MinGw x.x.x 32" suite for development under windows .. and "Android" component to develop Android Apps on Qt Creator.
Go down to the Tools tree, expand and select which components to download and install. For Windows usually you need : Qt Creator Debugger, MinGW x.x.x (same as above) and Qt installer framework (which is a maintenance tool for Qt upgrades ...etc).
If you have selected MinGw kit in Qt Version , then you must download the corresponding MingW framework, from Tools branch, unless you have it.
Note: with a clean installation of Qt, it configures itself automatically and no further configurations are needed -> Kits are automatically configured based on your installed components.