Applying to Anfield, ESF, ICS kindergarten

Hello my son is 6 months old now, and we plan to get into one of the kindergartens of Anfield, ESF, ICS (would prefer ESF and ICS as they have primary and secondary school).
Are there any preparation classes that will help our son to get into one of those kindergarten Maybe like the pre-k classes of Anfield?

P.S We are currently living in Mid-levels but planning to move to Fotan.

Thanks so much for your advice :)