Where can I convert USD to USDT?

I'm quite new to the world of cryptocurrency and finance, and I'm trying to figure out where I can convert my USD to USDT. I've heard that USDT is a stablecoin pegged to the US dollar, which sounds like a good option for me to diversify my portfolio. But the question is, where can I find a reliable platform or exchange that offers this conversion service? I'd like to know if there are any specific exchanges that are known for their efficiency, security, and low fees. Additionally, I'm also interested in learning about the process involved in converting USD to USDT, like whether I need to create an account, verify my identity, and so on. Could you please guide me in the right direction?