If you want users new to your stream to agree to a ruleset before they start chatting, you have to set up your own set of Twitch chat rules.
To get started, just head to your Twitch Dashboard, and on the left-hand side, you will see some tabs. First, click the settings tab, and a dropdown will appear. You can then click Moderation to go to your channel's moderation page.
Once on the moderation page, scroll down to the bottom to see a section dedicated to Chat Rules. You can enter all the rules you want people to acknowledge before chatting for the first time in your Twitch Chat.
If you need help thinking of what rules you can add, you could always check what your favorite streamers have, friends, or even Google to see what others recommend. I suggest, though, that you adapt it to your channel. For example, you would have a rule not to backseat a game when you’re a music/DJ streamer.
Basic rules like respecting the mods and everyone in the chat, not tolerating hateful conduct, etc., will always be relevant to most if not all, channels.
Once you are done with your rules, you can reorder, edit, or delete them with the icons next to the text box. Then, you can click Save Changes to apply the rules to your channel.
Here are some more articles you might like: