Should I learn Qt or WXWidgets

How to learn QT?

I would recommend that you learn the basics of C first. And then to learn Qt. You can learn it from books or the Internet, for example. What is also not bad is a course or similar, you can even do it from home, but it costs a lot of money (depending on the course and scope around 2000-4000 €) which can be worthwhile. The learning material (if it is well done) is easier to understand than in most books. The advantage of a course is that you can ask your responsible teacher anything. So you always have a professional who you can address (or write to) what you can't with books. You can also get a certificate (it's not necessarily wrong if you want to do something in the field later on)

I would be careful with books. There are a few good ones, but many are not suitable for beginners because prior knowledge is often required or some topics are only briefly discussed or not at all. You often have to look it up on the Internet (or elsewhere).
Unfortunately, I don't know of any good books specifically for Qt at the moment. But for C ++ the book "The C ++ Programmer" by Ulrich Breymann should be very good.

If you should decide on a book, I would recommend a more recent one (from Qt 5). Because there are some changes. If you buy a book about Qt 4 now, you may acquire things that are no longer possible in Qt 5. But it should be enough for the basics.

If you have any questions, go ahead