do i type in the root word for example [agr] in the search bar and then the word that start with the 3 same letters in the word is the word i use to look up

Type in agri-. Note that's a hyphen after the four-letter prefix.

agrivated

is the word homework a prefix

If you are looking for words that share a common root, typing in the root word in the search bar can be a helpful approach. However, it may not always guarantee the most accurate results, especially if the word you are searching for has undergone significant changes in spelling or pronunciation over time.

To find words that share a common root, you can follow these steps:

1. Identify the root word. In your example, the root word is "agr".

2. Use a dictionary or an online etymology resource to search for words that contain the root "agr." Look for words that start with "agr" as well as words that have "agr" within them.

3. Analyze the meanings and origins of the words you find. This will help you understand the common characteristics and connections between them.

Remember, the method of searching for words based on a root may not always yield the exact word you are looking for. However, it can be a useful way to explore related words and understand the etymology and meaning behind them.