By default, WhatsApp will automatically set your privacy settings to allow any WhatsApp user to view your last seen and profile photo. If you don't share your last seen, you won't be able to see other peoples' last seen. Please note there is no way to hide your online status.
To change these settings, simply go to WhatsApp > Settings > Account > Privacy.
You can set the following options separately for last seen and/or profile photo:
Your last seen and/or profile photo will be available to all WhatsApp users.
Your last seen and/or profile photo will be available to the contacts from your address book only.
Your last seen and/or profile photo will not be available to anyone.
To block any contacts that are stored in your phone, tap on Blocked in your privacy settings. For more information on blocking contacts, see this FAQ.
Your status updates cannot be seen by people whose numbers are not saved in your phone's address book. You can choose to share your status updates with all of your contacts, or with selected contacts only. By default, your status updates are set to be shared with all your contacts.
To learn more about Status privacy, see this FAQ.
You can turn off the Read Receipts feature such that you will not send Read Receipts for the messages you receive, nor will you see Read Receipts for the messages you send. If you have disabled Read Receipts, you will not be able to see who's viewed your status update. For more information, see this FAQ.
WhatsApp Support Team