From my personal experience
When I first wanted to start a business (after reading rich dad poor dad

) I was in a rush, I went online as most of us have and searched for cheap ideas to start a business. The same Ideas you have mentioned constantly popped up, window cleaning, man +van etc. I looked into these thoroughly and considered 1 or 2 of these ideas but then as time went on things changed.
I felt I was stuck as I have no qualifications and do not really any field I specialised in and would find people would say to start a business in your field but I had non.
One thing I realised, when you are in this situation you want quick money, but the reality of setting up a business is that it is a slow process. Initially I had no idea what to do, hence looking into these ideas
BUT as time went on, I started reading through this forum and other places on the net, which started opening up my mind and I began to see new business ideas all around me.
I would say the 2 main things which gave me clarity was
The concept of branding
and
True understanding of a USP
Understanding these 2 gave me a new set of eyes
I have not yet launched any of my businesses, but I have 4 - 5 which I am very very confident about and have even been asked by others to partner up. I am working and saving and planning. As time has gone on, I have tweaked my ideas to become better and I'm still constantly doing so.
My main principle I am trying to stick to is start with the least capital possible, but at the same time be realistic.
I am very happy that, the whole time I have been planning I have not had the capital that I initially wanted, as if I had then I probably would have rushed everything and flopped. Yes there is such thing as trial and error but no need to throw yourself into error if you can be smart about it.
YOUR PLAN FOR NOW
Find a job
work and save
Research Research Research
the rest will come in due time