I am going to Thailand and the tour includes several Budhas and temples. Can i look at them?
You would be well advised to avoid all such places. The Gemora says that Jews are not allowed to benefit from idols and avoda zara. Included in this are entering a place of worship of an avoda zara, such as their temples. This prohibition also included not to look at an avoda zara, or even a place of worship of an avoda zara, which would include not looking even at their temples. The reason for all of this is because the torah does not want us to any connection to avoda zara, and definitely not to benefit or do things that might leave a positive impression of such negative things. We Jews should stay far away from such places. The same way physically we would not want to walk near sewage dump, even if we aren’t walking inside of it, because even being close to it smells. Similarly, on a spiritual level, the torah doesn’t want us getting near such places and being influenced by them.
Other than that, enjoy the kosher parts of your trip.
Pesachim 26a, Shulchan Aruch Y:D 142-15, Chochmas Adom 84-16, Avnei Yoshpe 1 Y:D 153(4) in the name of R’ Eliyashiv zt”l, that we should even avoid looking at pictures of the inside of a church.