Land purchase - Newbie questions

[Mtgtme Mtgtme]

Hello, I am a newbie with real estate and want to see what one needs to check while purchasing the land.

1. Type of land: What is the difference between developed/zoned/undeveloped land? What is preferred?
Is it worth buying commercial-zoned land 6-8 acres or purchase undeveloped land of 25-30 acres?

2. What checks I need to do to protect the investment?

3. Soil testing: what to look for in the soil testing. Should I go with the seller report or do I need to get it done myself. what could be the red flags.

Any comments/experiences please share to educate me. If there are any resources I need to go through please guide me. TIA