The fix hacked wordpress database Codex has an outline of what permissions are okay. File and directory permissions can be changed through an FTP client or within the administrative page from the hosting company.
Hackers don't have the capability once you got these lined up for your own security, to come to your WordPress blog. You definitely can have a WordPress account that gives big bucks from affiliate marketing to you.
Should you ever want to migrate your website elsewhere, like a new hosting company, you'd be able to pull this off without a hitch, and also without having to disturb your old site until the new one was in place and ready to roll.
Note that this step for setups should try. If you would like to do it for installations, you need to change all the table names inside the database.
You don't always consider needing security, when your website is new but you do have to protect yourself and your investment. Having a site go down and not having the ability to restore it quickly may mean a major loss of customers who probably won't remember to search for your website later and can't find you. Do not let that happen to you. Back up your site as soon as you get it started, as the website is operational and schedule frequent backups for as long. That way, you will have WordPress this hyperlink security and peace of mind.