I'm a student and new to amateur radios. Is it legal to operate ham radios for educational purposes without any license?
As mentioned in a comment, if you ask a legal question you need to give us an idea of where you are. Please add a country tag.
However - this is one that’s not hard to answer without knowing where you are.
Generally, around the world, if you are to transmit as a radio amateur in any case apart from an actual emergency, then you need to be licensed in the country you are in when you transmit. Or have an amateur radio licence from a country that has agreements with the country you are in when you transmit that specifically allow you to do that.
It’s not like software licensing where you have to buy an expensive license but it’s “free for educational purposes”.
If you want to transmit, you need a licence.
There are many reasons for this, which you will learn in detail as part of the process of getting your licence.
The purpose for licensed ham radio in and of itself is education (whether for self or others), experimentation and for recreation. So yup, to transmit, you'll need a license (at least for the US and UK).
You can, however, listen to ham broadcasts without a license (at least in the UK, where I'm familiar with the laws)