bordering cells in a HTML table

Hi, I am trying to get cell borders between the boxes on my site. it shows up on the visual tab (in the editing screen) but when I go to view the website in a browser then it doesn’t come up.

I used the code for the border

<table style="width: 100%;" border="1">

Here is the link: https://www.thurrocktutors.co.uk/fees/

And the full code I used (editing out text):

<table style="width: 100%;" border="1">
<tbody>
<tr>
<th><b>Individual Tuition</b></th>
<th><b>Private Group Tuition</b></th>
</tr>
<tr>
<td style="width: 50%;">
<p style="text-align: center;">The rates for 1 to 1 private tuition at the centre are a.........
</td>
<td>
<p style="text-align: center;">Why not team up with your friends to spread the cost?.....<p>
</td>
</tr>
<tr>
<th colspan="2">Open Group Tuition</th>
</tr>
<tr>
<td colspan="2">We also arrange group tuition ....</td>
</tr>
<tr>
<th colspan="2">Home Tuition</th>
</tr>
<tr>
<td colspan="2">If you are looking ....</td>
</tr>
</tbody>
</table>