There are a number of ways you can hide the cell borders depending on your style sheet or which version of HTML you are using, but the easiest way, which will normally always work whatever version you are using, is to make the cell border color the same color as your background color.
For example you would change the code from this:
<td style="border: 2px solid #352ece; background-color: #add8e6;
To this;
<td style="border: 2px solid #add8e6; background-color: #add8e6;
Do this to all your cells and you will see this:
If you don't want the table border you can change the <table style> from this:
<table style="border: 3px solid #352ece;">
To this:
<table style="border: 3px solid #ffffff;">.
Don't need header, sub heads or column heads? Have a look the the next page.
Tables baffle a lot of people - I've seen a lot of questions here about them - and without a plugin, going into HTML for some people can be very daunting.You've clearly explained tables in a very easy way to understand.
If I could add one thing, where you have "width: 123px;" - that can be changed to a percentage - so your table becomes a little bit responsive. eg. "width: 40%;" - then the table will adapt as much as possible to the size of screen it's being viewed on.
All the best, Mark