This code:
\subsection*{4.1 1NF}
No, this table is not in 1NF as column Info can and on multiple rows hold multiple values. 1NF Variation would be:
\par
\begin{table}[]
\begin{tabular}{|l|l|l|l|l|l|}
\hline
{\ul \textbf{Student\_ID}} & \textbf{First Name} & \textbf{Last Name} & \textbf{Course} & \textbf{Credits} & \textbf{Grade} \\ \hline
1 & Adam & Brown & Databases & 5 & 8 \\ \hline
1 & Adam & Brown & Algebra & 3 & 7 \\ \hline
1 & Adam & Brown & Algorithms & 5 & 9 \\ \hline
2 & Felicia & Green & Algebra & 3 & 10 \\ \hline
2 & Felicia & Green & Programming & 5 & 6 \\ \hline
3 & Mary & Grey & Databases & 5 & 9 \\ \hline
3 & Mary & Grey & Algorithms & 5 & 7 \\ \hline
3 & Mary & Grey & Web & 3 & 10 \\ \hline
1 & Adam & Brown & Physics & 3 & 10 \\ \hline
\end{tabular}
\end{table}
Produces this result:
Rednder of the LaTeX code above
But I need the table to be after the text.
Can someone tell me what am I doing wrong?
You're missing a floating specifier, e.g. to allow the table [h]ere, at the [t]op, at the [b]ottom or on a separate [p]age:
\begin{table}[htbp]