Configuration changes with multiple standby nodes

# DB Version: 10.5

# OS Type: CentOS 7

# Total Memory (RAM): 32 GB

# CPUs num: 24

# Data Storage: ssd

https://pgtune.leopard.in.ua suggested me tuning config as below

I have two questions regarding this

1. What changes do I have to do if I add more standbys or it will be same over all servers?

2. How to select a value for max_connections based on the fact I have 3 servers with same specs and client will using it for read operations only and data is loaded once a month.