Hann notar rakvél á morgnana, en hún notar rakvélina á kvöldin og vill hafa meiri froðu.

Because á morgnana and á kvöldin describe a habitual, repeated time: in the mornings and in the evenings.

By contrast:

• í morgun = this morning
• í kvöld = tonight / this evening
• á morgun = tomorrow

So this sentence is talking about what they usually do, not about one specific morning or evening.

In Icelandic, repeated times of day are often expressed with a plural definite form:

• á morgnana = in the mornings
• á kvöldin = in the evenings

This is very natural in Icelandic. It is not saying there are some specific separate mornings already known from context; it is just the normal way to talk about a regular pattern.

This is the difference between indefinite and definite:

• rakvél = a razor
• rakvélina = the razor

Icelandic usually adds the definite article to the end of the noun, instead of using a separate word like English the.

So:

• Hann notar rakvél = He uses a razor
• hún notar rakvélina = she uses the razor

Both are involved.

The verb nota takes a direct object in the accusative case. So both rakvél and rakvélina are objects here.

The important thing is:

• indefinite accusative singular: rakvél
• definite accusative singular: rakvélina

Learners often do not notice the case in rakvél, because that form looks the same as the basic dictionary form. But rakvélina clearly shows both definiteness and accusative.

Both verbs take the accusative for their direct objects here.

Examples from the sentence:

• notar rakvél
• notar rakvélina
• hafa meiri froðu

A very useful thing to notice is froða. Its accusative singular form is froðu, so here the case change is visible.

Because meiri has to agree with froðu.

The word meiri means more and is the comparative form of mikill. Unlike English more, Icelandic forms still change for gender, number, and case.

Here:

• froða is a feminine noun
• after hafa, it is in the accusative singular: froðu
• so the matching form is meiri

That is why meiri froðu is correct.

Froða literally means foam, froth, or lather.

In this sentence, because the context is shaving and razors, it naturally means something like:

• shaving foam
• lather
• possibly shaving cream, depending on context

If someone wanted to be more specific, Icelandic can also use words like rakfroða for shaving foam. But plain froða works well here because the context makes the meaning clear.

Because the subject is still hún, and Icelandic often omits a repeated subject in coordinated clauses when it is obvious.

So these are both possible:

• ..., og vill hafa meiri froðu
• ..., og hún vill hafa meiri froðu

The shorter version is natural because the subject has just been mentioned and there is no confusion about who vill hafa meiri froðu.

Yes. The word order is completely normal.

The sentence has two main clauses joined by en:

• Hann notar rakvél á morgnana
• en hún notar rakvélina á kvöldin

Then a further coordinated part:

• og vill hafa meiri froðu

A useful thing to remember is that Icelandic is a verb-second language. If you move something else to the front, the verb usually comes next. For example:

• Á morgnana notar hann rakvél.

So the sentence as given is straightforward and natural.