table by default dont have border, so you need to add it by yourself using css styles.
https://www.w3schools.com/html/html_table_borders.asp
not sure what you mean by fill it in, you set data of table using <td>your data</td> tag
format to make table in html is
<table>
<tr>
<td>data you wanna display</td>
</tr>
</table>
this will make table with 1 row and 1 data/cell
if you think about adding data by clicking on cell, like we do in excel for example, you can set input field inside td like
<td><input type="text/></td>
