Most comments seem to be focused on the logistics of applying and financial concerns. Those are important, but before that I would strongly suggest you evaluate your reasons for doing the program and understand your commitment. For one, interviews and applications will want to know this anyway, and two, these reasons can be tested when things get difficult.

A few insights: school has changed in the last few decades. Things are more lean and there is more expected from students. A big divide if you consider a PhD program is whether it is a researched based (eg R1) or teaching school. A research based school is more competitive and honestly feels like a business sometimes. How many papers can you crank out? Can you devote extra time to helping research professors so that you get better opportunities?

There is a changing (and unclear) landscape of software. Sources libraries and PDF organizers can be helpful. Most the students I know are using some form of AI to read or write papers, and they make edits and such. There is ongoing debate on the ethics, but people are using it regardless. If the precedent becomes writing papers at the efficiency of using AI to structure the papers, the level of expectations again rises.

Also be sure to have a support system in place. Things can get overwhelming and frustrating, and leaning on people when needed will be important.

Start with really pondering your reasons for doing the program and see if a program would fit those needs. And it would be a great idea to reach out to current students at least a couple of different schools to get their input on how the program is. There is only so much you can gain from reading the website. If it is really what you want to do, start looking at the requirements and email the program director or assistant to see if you’re missing anything.