How to change Debug version (from 5.6.2 to 5.7.0) in existing project?

[time]

Hi!

I have a project and it is working fine with Qt 5.6.2 MSVC 2015 64bit. But now I want to add charts (i.e. PieChart) and I need have Qt 5.7.0 I have installed it on my computer, because in new project I have this option.
So my question is how to change Debugging from Qt 5.6.2. to Qt 5.7.0 in existing project and not to spoil everything?
I presume I have to change something in Tools -> Options -> Build and Run -> Kits and select Qt 5.7.0 as default, but before I will do this (because I don't know if it is ok) I want to ask here.
I use Windows 7 and C++

Now I have this:
12211

And I need this:
12212

and my Kits look like this
12213

[ChrisW67]

Get the kits right.
Open your project.
Click on the Projects tool icon in the left toolbar.
Add and remove the kits you want from the project.
Rebuild using the new kit.