Do I have access to this my.cnf?

After you realized that you need to change these settings you need to edit "my.cnf" file on your server (in most cases it in in "/etc" folder) and add the foollowing lines in "[mysqld]" section of the file, if the same configuration options already exists it is better to comment out old ones (with hash # symbol ) and add new ones near them:

If you have a dedicated or VPS then yes. You should have access to that file via a shell(command prompt). You will not have access on shared hosting.