Not all websites are suitable for use in your assignments so you need to choose your sources carefully. When you are using a website for your studies, it has to satisfy certain criteria. You should only use reliable, authoritative websites that comply with copyright requirements. Some of the questions you need to ask about a website are:
Who is responsible for the website?
When was the website created or last updated?
Check out the date the information was posted or the date the website was updated. If a website has not been updated recently, it may mean that the information is not up-to-date or the site is not maintained.
This is sometimes an indication that the person writing the website may not have the skills to evaluate and present information. It also is a sign that the content of the website has not been through an editing process.
In the end, you have to decide whether the information is useful or not. Does the writer provide evidence to back up what is on the website? Can you find other places where this is discussed?