Yes, this is a very straightforward main clause, and the word order is close to English:
So the structure is basically:
Subject + verb + place
That is one reason sentences like this often feel familiar to English speakers learning Afrikaans.
Here op corresponds to English on.
In many contexts, op is used where English uses:
In this sentence, it marks location: the object is positioned on the side panel.
So yes, op is a very common preposition, and on is usually the best first association to learn.
Yes. Both look like typical Afrikaans compound nouns.
Afrikaans, like Dutch and German, often forms longer nouns by joining smaller words together into one written word.
For example:
A useful rule for learners is:
So the ending of the compound often tells you what general kind of thing it is.
A rough English-friendly pronunciation would be:
dee LYE-loh-per is awp dee SYE-pah-neel
A few helpful notes:
This is only an approximation, but it should help you get close enough to be understood.
No, not in normal standard Afrikaans.
You need is here because this is a basic linking/copular sentence:
So Die laailoper op die sypaneel by itself would not normally work as a complete statement. It would feel more like a noun phrase than a full sentence.
You would make the nouns plural, but the verb is stays the same.
For example:
Important point: Afrikaans verbs are much less heavily conjugated than English verbs, so even with a plural subject, is still remains is.
That often surprises English speakers at first, but it is completely normal in Afrikaans.