Takfir — ruling that a specific person has left Islam — is a grave matter of Islamic law that belongs to qualified scholars applying strict conditions, not to individuals reacting to sins or disagreements. The Prophet ﷺ warned that whoever calls his brother a disbeliever, the label returns upon one of them if it is undeserved. Ahl al-Sunnah distinguish between condemning an act or statement of kufr in general terms and passing judgement on a named individual, for whom impediments (such as ignorance or misinterpretation) must first be removed. Reckless takfir is the hallmark of the Khawarij and leads to bloodshed, which is why the Salaf were extremely cautious about it.
Evidence — the daleel
Sahih al-Bukhari 6104 ṢaḥīḥSahih Muslim 60 Ṣaḥīḥ
On deen2u
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.