1. Do I need to adjust the platform after each resin print? You take it off and then use spatula or other to take of prints from the platform. Do you people need to readjust it?

No, not unless you didn't tighten the platform well enough or really torqued on it.

2. Do you really have to pour new resin after each printing and filtering the resin after each print? Even if it takes small amount of time to print?

It is best practice, if you have some tiny chunks of cured resin they could be pushed down onto your lcd screen and cause damage. However, I don't bother if I'm sure my previous prints came out without any problems.

3. Do you use same resin and keep printing? No one mentions these things... weird..

Yes, but it's best to stir it up when adding more

4. Is it pointless to wash nitrite gloves after you use it? Seems very unfriendly enviromentally if you use it for 10seconds while taking the print out and clean up.. All I feel it takes around a 1 min of use.

You can wash the gloves and reuse, but the alcohol used to wash the gloves cost more than another pair the gloves. Latex gloves are biodegradable, so you aren't saving the earth by reusing them.

5. Ive seen a guy who washes the resin tank after printing one puny, tiny model.. Cant you keep printing or you must wash it after every tiny piece of thing you just printed?

You don't need to wash every time, this is especially true if you can print on another part of the bed. If you print on the same part of the bed as a previous print without washing you may risk losing some detail due to residue buildup, but frankly it's a very minor concern.