I had one like this for years. When you dispose of the old plugs, try and keep the plastic parts. You can cut them some to get the roots out, but at least the top half. You can buy rock wool and other substrates to grow your own seeds, and the plastic part can be handy to keep the new substrate in place.

Have fun! These are really quite easy to use and fun.

Fyi "basil" is not the same thing as "thai basil"