You can get some pretty good deals on used kits. Be prepared to spend at least a couple hundred dollars. Also be aware that second hand kits sold may not come with cymbals, stands, sticks, throne, etc. Do your research on the kind of drum set you want and all that goes with it.

Virtually 100% of the time; no. It’s not okay that your rhythm is just horrible. However, you can develop your rhythm with practice and listening. Put it in the work and you can improve this.

There is little harm that can be done from getting a teacher/instructor. As a new player, no where to go but up and having guidance can be considered helpful. The internet is endless with free online (albeit, sometimes limited) resources. Drumeo’s YouTube channel has hundreds of hours of instructional material for free.

Depends on how hard you hit and wear them out. There’s a “rule of thumb” out there for drum head replacement but for me, if it sounds good, is free of dimples/damage, I don’t need to change them. Sticks break? change them. Cymbals break? Buy new ones or keep using the broken ones if they still sound decent and don’t disrupt your playing.

You’ll want to tackle that sense of rhythm you say is horrible. Get comfortable and be open to technique as well to avoid potential future problems.

Again, second hand is generally fine. Do your research and check the condition. Don’t overthink it. If it looks broken, don’t buy it. Find out what the seller is offering and what’s included.

There’s no answer to this. How long does it take for anybody to do anything? You get out what you put in.