You run the whole query, just like it is written:
INSERT INTO setting VALUES ('', 8, 'Minimum Characters per post', 'postminchars', '0', 'The minimum number of characters that you want to require per post. Set this to 0 to disable it.', '', 7);
in phpmyadmin, which you should be able to get to from your server. If not, talk to your host and they will tell you how to get to phpmyadmin.