How do I access my Exchange server?

I'm curious to know, could you please explain to me the process of accessing my Exchange server? I'm having some trouble navigating the steps and would appreciate a clear, step-by-step breakdown. Is there a specific program or software that I need to use, or are there any specific login credentials I should be aware of? Additionally, are there any security measures I should take into consideration while accessing my Exchange server? Thank you for your help.