I'm trying to call this class which uses @Future with a trigger. I'm unsure how to reference the class in the trigger. Also, since I am attempting to trigger the code with a field change it is difficult because I can't have the callout execute after an update. So, I'm not sure what trigger context should be used as well. 

Here is my trigger : 

trigger Trigger_ProgramContactRole on Program_Contact_Role__c (after insert, after update, before insert, before update ,after delete) {
    //Checking for the event type
    if(Trigger.isAfter){
        
        
        if(Trigger.isInsert){
                     
                        
        }
        
        
        if(Trigger.isUpdate){
                     
            
            
        }

But I don't know how to start this class with it : 

public class UpdateContactPCRController {

    @InvocableMethod
    public static String  updateContact(String recordId){        
       
        String contactId = '';       
        
        List<Contact> contactToBeupdate = new List<Contact>();        
        
        if(String.isNotBlank(recordId)){            
            
            List<Program_Contact_Role__c> programContacList = [SELECT Id,Contact__c,Program_Name__c FROM Program_Contact_Role__c WHERE Id =:recordId AND Contact__c != null];
            contactId = programContacList[0].Contact__c;
            
            if(String.isNotBlank(contactId)){
                
                contactToBeupdate = [Select Id,Pardot_Action_Trigger__c,PCR_Register_Button_Link__c,PCR_URL_for_UI__c FROM Contact Where Id =: contactId Limit 1];                
                
                contactToBeupdate[0].Program_Contact_Role_Id__c = recordId;
            }
                        List<Program_Communication_Recipients__c> programCommunicationRecs = [Select Id,Name,
                                  Program_Communication__r.Program__r.Buyer__r.Name,Receipient__c,                
                                              From Program_Communication_Recipients__c Where 
                                                           Program_Communication__r.Program__c =: programContacList[0].Program_Name__c AND 
                                                           Receipient__c =: programContacList[0].Id];                                           
                                
                
                    contactToBeupdate[0].PCR_Welcome_Message__c = String.valueOf(programCommunicationRecs[0].Program_Communication__r.Welcome_Message__c);                                                    

 pardotCallout(contactToBeupdate[0].Id);
    {

        @future(callout=true) 
        public static void pardotCallout(String contactId) {
            String returnedResponseFromPardot = Http_Utility_Pardot.pardotCreateProspect(new Set<Id> {contactId});
            // new treatment here with the returned value included DML operations.
    }

        if(contactToBeupdate.size() > 0){
            update contactToBeupdate;  
        }
        
        return 'Updated Successfully';
    }
}