To disable read receipts on your iPhone, you can choose to turn them off for all contacts or just for a specific individual. Please note that this feature only works when iMessage is enabled for both the sender and the receiver.
To disable read receipts for everyone, open the Settings app on your iPhone. Navigate to the Apps section, select Messages, and then toggle off the option labeled Send Read Receipts. Once this is turned off, senders will no longer see the status that your message has been read.
If you prefer to only hide your read status for a specific person, open the Messages app and select the individual conversation. Tap on the contact's name at the top of the screen to access their information, then find the Send Read Receipts toggle and turn it off. Keep in mind that if you disable this feature for a specific contact, you must re-enable it manually if you wish to see their read receipts in the future. Disabling this feature globally also prevents you from seeing read receipts sent by other users.