"@Yusha" السلام عليك
based on the hadith you mentioned about reciting after wudu and asking the following:
so if a person do less deeds or doesn't do other optional good deeds
like sunnah prayer etc, and just recite that after wudu will he still
get Jannahtul Firdaws? doesn't that makes it easy to get?
the hadith mentions gates of paradise not ...
The hadith of wudhu does not indicate that the person will be able to go to Jannat-al-Firdaws only for that action.
Rather the Prophet (SAW) says:
فُتِّحَتْ لَهُ ثَمَانِيَةُ أَبْوَابِ الْجَنَّةِ
All eight gates of Paradise will be opened for him.
The gates of Paradise do not correspond to the levels of Paradise. Meaning, it isn't like one gate will lead to ...