Namu Amitabha Buddha or Namu Myōhō Lotus Sutra

I think it feels better than shape.

The shape was decided by humans after all.

Please put your hands together.

Hello.

A few years ago, when I went to pray at Zenko-ji Temple in Nagano, the guide said, “Zenkoji is non-denominational, so it's fine if it's Namu Amida Buddha or Namu Myōhō Renge Kyō, or even amen.” There are exceptional temples like that, but I think many people pray with their hands together at shrines, and cross their fingers at Christian churches.
In that sense, if you're going to a temple of the Nichiren sect and chanting something, I think it's a good idea to chant “Namu Myōhō Renge Kyō.”
Also, it doesn't mean you have to chant something in front of the temple's principal image, so I think it's fine just to quietly put your hands together. There are times when people pray at temples where they don't know their denomination.

Incidentally, the rosary differs depending on the denomination, but I don't think it is necessary to match this with the sect you are praying for. It is good if you have one rosary of the denomination you believe in.

If it's a temple of the Nichiren sect, I think it's a good idea to sing Namu Myōhō Renge Kyo. Since it's the Jodo sect, it doesn't mean you have to sing Namu Amida Buddha everywhere. I think it's a good idea to adapt to the situation.

Excluding all of the doctrinal teachings of the sect called the “00 Sect of Japanese Buddhism,” when viewed globally (objectively) from a pure Buddhist viewpoint (without sect color), both Amida Buddha and Myōhō Renge Kyō are nicknames for the natural nature of oneself, and also nicknames for the human Buddha's heart.
The true religion and true Buddhism of humans is different from Buddhism, where there are factions (although not separately), where the origin is Buddha, and since the origin is the Buddha, there is also an aspect where there is no separation no matter what you say in terms of the act of “worshiping,” which respects the Buddha's heart, and is aware of human selfishness and nature.
If you imagine Buddha saying “Namu ○○,” you'll even feel a sense of incongruity.
Since the origin of Japanese Buddhism is all Buddha in the first place, the ideal of Buddhism is to reach the point where the Buddha learned, and in terms of equalizing one's own heart with the Buddha's heart of wisdom and compassion, separating them by a barrier “because of the 00 sect” and “because of the ○○ sect” and making them “something else” is probably something that even Buddhism will disappear in a deep sense.

But even so, if you take 100 steps back, it's something humans do in the human world. No matter how much you call it Buddhism, the Buddhist world is still divided into sects, and there is a current reality where each exists separately and independently, so it is also important to take into consideration that there are people who live “separately” as individual things within such a framework. True religion is only when there is an attitude of mutual respect and dignity.
Oppositional, aggressive religions, and religions that fight or fight oppress other religions, so they cannot be called religions. It is called a thought organization.
A good religion is one that respects other religions.
There is a shrine in the precincts of a certain temple, but it will never be destroyed.
At 00 Temple, the head temple of the 00 sect, we respect Kojin, who was the god of kamado, and Badger Inari as guardians who protect the temple grounds.
Other religions would have been destroyed a long time ago, but they coexist.
That's why they respect and praise the traditional indigenous gods.
Toyokawa Inari, which was the chief priest of the current Zenji heiji of Eiheiji Temple, also enshrines Inari-sama.
Japanese temples have such a ❝ measure ❞.
That kind of attitude means “there will be no harm.”
I think the founder and Buddha will also be delighted by being scolded with a heart that does not cause such disputes or divisions.

A Zen monk who likes to be silent mutters bluntly, saying that worshipping in silence is versatile...
I left aside what I said... I didn't need...

If you do that, it's a mistake; if you do this, you don't pray for a mistake and point deduction method,
Let's say thank you if you do that, and say thank you if you do this, say thank you.
If the number of people who can pray like that increases, it will surely become a comfortable society to live in.

Kimi3

This is Kawaguchi Hidetoshi. This is my humble answer to the question.

There are differences in denominations, but they are convenient differences for enlightenment, and enlightenment, which is what we should aim for, is the same.

It's not that your own denomination is the best, and it's important to respect the teachings of each denomination as Buddhism, which is the Buddha's teaching.

When you go to each place, you are required to respect the teachings of each place and learn and practice for the purpose of enlightenment.

By all means, if you pray at a temple of the Nichiren sect, you will be chanted “Namu Myōhō Renge Kyō,” and I hope you learn a lot from that teaching.

Kawaguchi Hidetoshi Gassho