Using a nose clip while swimming is a matter of personal preference. Some elite swimmers opt to wear them to prevent water from entering their noses, which can enhance their underwater phase.
There’s nothing wrong with wearing one, but you’ll be so in love with yourself and feel even more free when you can go in whenever you want without one.
Some folks, especially beginners, love them because they keep water out of your nose. This can make it easier to focus on breathing through your mouth only while you learn proper swim technique. I don’t use one myself anymore, but I can see how they’d be helpful at first. Eventually, most swimmers want to develop good breathing technique without a clip. If you’re just starting out, give it a try and see if it helps you feel more comfortable in the water!
It depends on your preferences and swimming goals BUT nose clips are not essential for everyone who swims.
Nose clamps are a must if I swim in lake water because I have terrible allergies to it. Don’t let other people’s opinions stop you from making changes if it upsets you.