Demo or not it should be at least working properly, & designed to look & feel how it is supposed to be, that's a bit like baking a cake and asking people to try it before it's fully cooked.

It's also an attempt to emulate a profile of a gentleman called Pascal van Gemert (hope you got permission to use his image)

Stefke,
You are suggesting that you are working on this webpage for a customer.
The best advice I can offer to you: stay away from customers at this stage of your learning curve.
I suggest that you also stay away from Site Designer for a while. First learn some of the basics of how to design a website (purpose, goal, audience, usability design, graphic design and so on). Best to use pencil and paper to start with.
Then go to w3 schools and learn the basics: https://www.w3schools.com/whatis/default.asp.
After that, go back to Site Designer, build a simple one page website (no fancy grids) and then - in a few years - come back to this forum and ask for help if you have problems with the use of SD.

Note: if necessary I can translate this message in Dutch language for you.

We have had a lot of language issues during the years when trying to help Stefke. Especially, if he uses the service vertalen.nu, it seemed to procuce a certain amount of 'gobbledigook' While helping him with the taxi site some 2-3 years ago, I had my English translated by Google translate. I don't know how good it is, but at least we got the site done.

So, what I'm saying, Dutch is probably better. But it takes time to do everything bilingually.