It is not necessary to have a CFA (Confirmatory Factor Analysis) before using SEM (Structural Equation Modeling) in PLS (Partial Least Squares). While CFA is commonly used in SEM to assess the measurement model and ensure the validity and reliability of the latent construct.

If you have an adopted scale that has been previously validated and widely used in literature, it is not necessary to run an Exploratory Factor Analysis (EFA) or Confirmatory Factor Analysis (CFA) again. The purpose of EFA and CFA is to establish the validity and reliability of a measurement scale. However, if you suspect that the scale may not adequately measure the constructs in your specific context, or if you have modified the scale in any way, it may be beneficial to conduct an EFA or CFA to assess the psychometric properties. Good Luck! 💐

CFA and EFA are done in amos and it only reflects the validity of the scale if you have adapted the scale then it is good to have this, but if you have adopted the scale and scale is well established then no need.

If you adopted the pre validated scale without making any change in the scale items, then there is not need to run EFA and CFA .