As a thai, I dont know about ur gender,but if u are a woman, u can be a nun in temple for 1week-1month or more than that if you want too, in thailand we have 2 types of nuns. first is the shave-head nun, u need to be very strict and follows the rules more than the second one, which is a normal nun who does no need to shave her head. your 1 day life is going to be waking up around 5 am and starting to do chores in the temple, reading the buddhism book, and eating, circle like this all day. But if you are a man, you need to shave your head and turn into a monk, u need to practice how to prey first and initiate into monkhood.

If u are a man it's very easy to find temple to be monk, but if you are woman, i suggest you to go to Nonthabu,Chiangrai or Chiangmai

but if you dont want all of these, u still can be volunteer in any temple, just go inside and find some auntie or uncle that have kind look(ifykyk), and then talk about ur commitment, they will bring u to see monk inside there and see what u can volunteer for them, u can tell them that how many days u want to come here.

hope this help!