How to mark points and lines on an XY (scatter)

Hi. I am trying to create a body temperature chart for a patient in Libreoffice Writer.
The X axis consists of the days hospitalized (0-15), while the Y axis consists of temperature (36-40o C).
I am having trouble working within the chart at all, most notably noting points of temperature corresponding to each day of hospitalization, and further connecting each by lines creating a fever chart.

Any ideas?

Thanks in advance.

Context info:
LibreOffice version 4.3.2.2, English, Writer.
Windows 10, English.

I have answered below using an understanding of the term “days hospitalized” being a linear progression i.e., temperature reading on day 1, then day 2, and so on. It is not entirely clear if this is what is meant. The question may need editing to provide an example for clarity.

Use a Line chart. The X axis is a linear series of days (category label), rather than a value series where each data point relates to the corresponding y data. An XY (Scatter) chart uses related value (x,y) pairs e.g., temperature vs blood platelet count, hence the term scatter. These value pairs can still be recorded against a category label (date) but this is not the case in this instance.