Some things to do Immediately - all for free
Run the Carbon Footprint Checker
Run your website through a vulnerability checker
Run Chrome/Lighthouse on your website (Mobile first / desktop second)
Run a Crawler / link checker e.g. Download https://www.screamingfrog.co.uk/seo-spider/ or use https://validator.w3.org/checklink online
Accessibility checker – Chrome or Firefox have good built in or add on extensions – there are some automated checks, others are manual or subjective, guidance usually provided. Or use Google Pagespeed for accessibility and three other measures.
Review any third-party website provider contract (are updates included)
Password strengths
Try https://www.passwordmonster.com to check your password strength and consider using a Password Vault or two factor authentication system. These are now usually built into operating systems as options. A minimum password length is now regarded as 8 characters (and better if a mix of cae, special characters and alphanumeric characters.
There is a built-in password manager in Windows 10, but it's named “Credential Manager.” You can view your saved passwords any time by searching in settings for the credential manager. To view a password, you need to enter your PC's PIN. It's easy to use, but it might not be the most secure option.
The Apple password manager, known as iCloud Keychain, is an option built into every Mac, iPhone, and iPad which can be used to generate random passwords, store passwords and usernames, store credit card numbers, and autofill information when you return to the same website.
For Manage your saved passwords in Android or Chrome based devices passwords are securely stored in your Google Account and available across all your devices.
On Ubuntu, you can also manage your passwords and secure your online activity by using the built-in password manager. This will help you to better organize your passwords, create secure passwords as needed, and lock down your accounts with two-factor authentication.
Other password vaults and two factor authentication tools can be separatley sourced and may have other options with more functionality.
Make sure you use a screensaver with a password required option set and a short duration period say 5-15 minutes, so when you leave your PC unattended the screen will lock and require a password to open back up.
Others
Manage your reviews
Does your website support a Friends / Members area?
Try ChatGPT (requires you to register but free at the moment)