Asalamoalikum! Hope you will be will and doing your best for Islam. Brother there is a hadees in munad ahmad 22978 "O people, your Lord is one and your father Adam is one. There is no virtue of an Arab over a foreigner nor a foreigner over an Arab, and neither white skin over black skin nor black skin over white skin, except by righteousness. Have I not delivered the message? " So brother can you give me complete reference of this Hadith and also it's status because I came to know that Munthir ibn Malik, whom Al-Bukhari quoted in his mu'allaq (suspended) hadiths so please also also tell me about mu'allaq Hadith.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Regarding the hadeeth, “O people, your Lord is one...”, if you wish to delve into its narrators, you can refer to hadeeth number 2700 in Silsilat Al-Ahaadeeth As-Saheehah by Shaykh Al-Albaani where he extensively discusses those who transmitted it among the hadeeth scholars. As for your inquiry about “mu'allaq” hadeeths (those whose chains of narrators are omitted), if you mean Al-Bukhari’s Mu’allaqat - as it appears from the question- then Al-Bukhari’s Mu’allaqat are what was narrated by the Prophet without Isnaad (chain of narrators), or the beginning of its Sanad (chain of transmission) was omitted. These hadeeths do not have the status of fully attributed ones; some are authentic according to al-Bukhari's criteria, while others are authentic without his criteria and some are argued about it.

As far as we know, the Hadith mentioned in the question was not mentioned by Al-Bukhari in his Saheeh as Mu‘allaq Hadeeth.

Allah knows best.