How do I transfer bitcoins from a bank account to a bitcoin exchange?

Hello there, I'm curious about the process of transferring bitcoins from a bank account to a Bitcoin exchange. Can you guide me through the steps involved? I'm particularly interested in knowing how secure the process is, and what are the potential fees that I might have to pay. Additionally, I'd like to know if there are any limitations or restrictions on the amount of bitcoins I can transfer. Thanks in advance for your help!