There are total 24 Avataars but as per Pushtimaarg we celebrate only 4 Avataars festival [1] Narsinh Avataar [2] Vaaman Avataar [3] Raam Avataar [4] Krishna Avataar.
However for all avataars these can be found in all different Puranas. From these 4 Avataars only Krishna Avataar is Purna Purushottam Avataar.