how exactly are space and time entangled? How could time be defined? Many times I heard people who actually work with physics say that time is just an illusion (didn't feel like they were joking [???]), and then I hear about theories that say the more you'd approach to the speed of light, the slower time would pass. Things such as time doesn't pass to a proton. All I can think of it is Einstein's scene in Rick&Morty screaming I WILL MESS WITH TIME!!!!! I WILL MESS WITH TIME
This is really hard to imagine, but space and time are the same thing (as far as I understand); “space” has 3 dimensions - length, width, height - and time is essentially the 4th dimension. Time is an illusion in the sense that it’s not constant for everyone; time flows at different rates depending on the speed of the observer and whether or not they’re in a gravitational field.
What you’re referring to with speed affecting speed of time is the theory of relativity; you move faster through space and slower through time. And yes, you’re right that photons don’t experience time, since they’re traveling at the speed of light, which is the fastest obtainable speed. Relativity is really crazy and hard to wrap your mind around, so don’t panic if you’re having trouble understanding it. Feel free to hit me up if you’ve got any questions!!