No. "Wahhabi" is a label applied by others to the reform call of Shaykh Muhammad ibn ʿAbd al-Wahhab, who did not found a new sect or madhhab but called people back to pure tawhid (worshipping Allah alone) and the removal of later innovations, while himself following Hanbali fiqh and the Athari creed of Ahl al-Sunnah. Its foundation is simply the purpose Allah states for creation: "I did not create the jinn and mankind except to worship Me" (Quran 51:56), and the command "So worship Allah, making the religion sincerely His" (Quran 39:2). So the correct framing is that it is a call to the manhaj of the Salaf, not a twenty-first branch of Islam.
Evidence — the daleel
On deen2u
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.