What are the requirements and procedures after obtaining a Non-Imm O-A visa in Thailand?

For all of you who make hotel booking. I see most hotels gives you form to fill your credit card information for authorization. I WARN YOU TO NEVER DO THAT ! IT'S SERIOUS DANGEROUS !. That is not the way how to pay with credit card. Hotel must send you SSH link for payment process. And there you can type all your data securely. If you send via email, your data can be leaked every where around the world. And the hotel's staff can also see all the information you provide and with that info, someone bad can use it for online shopping !. Credit card company will not responsible if you provide your credit card's info in that way.

I don't know why they required customers to do it so. Stupid or maybe pretending to be stupid.

You will find there's no convenient list of what you are required to do when staying in Thailand, and every immigration office has its own local "agenda". Your best strategy is to join a Facebook group which represents the area in which you are living or intend to live, as the group members will be in the best position to advise.

On arrival you will get a stamp for 12 months or as long as your insurance is valid for. You need to ensure your landlord (or hotel) file a TM30 within 24 hours of your arrival and every 90 days inform immigration of your location. Once you have done one 90 day report in person you can do later ones online using a web browser or phone app.

90 day reports, yes. Registering where you're staying, that's another.

Beyond that, every local area seems to vary requirements. The advice you get from Phuket may vary from Chiang Mai etc. Pop into your local immigration office for their local requirements