Irfan View is a great program, but it will not do what is asked for - at least not without a lot of cunning that I don't know about. Please enlighten me how to put an old head on young shoulders; or a fresh face on world weary shoulders perhaps?
One could perhaps start with Windows Paint. That has a scissor tool to cut out shapes and move them around, but it really is kids stuff. To produce anything remotely realistic you will have to get to grips with something like Paintshop Pro.
How far did you get? Did you download and install it OK?
I do not know of a free programme that will do what you ask; i.e. a photo montage.
If you wish to do this, then I am sorry to say, its "bite the bullet time", and purchase a programme. There are a number of programmes that will do this, including Microsoft Picture-It. This is a very simple to use photo manipulation programme; ideal for beginners.
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