How can I get notifications on my iPhone 13 instead of Apple Watch?

Don't wear the watch when you need the Notifications on an iPhone.

Where notifications appear

Notifications appear on your Apple Watch or iPhone, but not both.

Customise your Apple Watch notification settings

1. Open the Apple Watch app on your iPhone, then tap the My Watch tab.
2. Tap Notifications.
3. Tap an app to see its options. ... 
4. If you customise an app's notifications, you can also group notifications from that app.

Notifications on your Apple Watch - Apple Support (IN)

Probably as a battery conservation measure, it doesn’t work the way you were hoping it would.

Notifications go to the device that is unlocked and awake. If you put your Watch in Do Not Disturb, it should go to the iPhone if it’s with you. Test it.

penni272 wrote:

But I want to receive on both at the same time

You may want it, but that's NOT how Apple designed notifications to work when wearing Apple Watch. If your iPhone screen is locked, notifications are delivered to your watch. If your iPhone screen is on, notifications will be delivered to your iPhone. But notifications will NOT be delivered to both at the same time and this how Apple designed it to work.

When I first started wearing Apple Watch, I thought this was strange. But I now really appreciate how it works. People around me appreciate it even more as both my phone and watch don't make a sound at the same time. And I actually don't use sounds for notifications on my Apple Watch. I use Strong Haptics, which taps my wrist with enough force to make me aware a notification is being delivered and no one near me is aware of that at all.

That's not how it was designed to work.

penni272 wrote:

But I want to receive on both at the same time