How so I keep my text messages to only sending to my iPhone?

My friends are texting me but I can't tell because the messages are already being opened because they are being sent to my dad! I did a software update but that Shouldn't make a difference. I set it as to only be sent to my phone and I went to settings and under messages and it's still set to only my number

Check your call forwarding settings and text message settings and make sure they're set to your number only.

Call to I phone helpline

You need to change the apple id on your personal iPhone. Stop using your dad's apple i.d. On that phone.