This is my opinion about your sentence: Quiza tu le cáes bien a la gente a primera vista, porque eres una persona amable, o físicamente agradable, o tienes muchas cualidades, por eso la opinión de la gente es positiva acerca de ti, pero para ti no es fácil dar una opinión de los demás cuando no los conoces lo suficiente.

This means that is easy to be loved by people when you let them talk about you or give an opinion about you, and you never give opinions about them (what they do or who they are...) Hope it helps!

"It's easy to get on well with people when they can give their opinion about you but you can't give your opinion about them" Basically, it's telling you that it's easy to be liked by people if you accept their criticisms and their opinions about you (whether they're good or bad) but you have to keep yours to yourself so they don't get offended. The sentence is complex but it's gramatically correct as you wrote it, however, there are some orthographic mistakes: "Es fácil caerle bien a la gente cuando ellos pueden dar su opinón de ti pero tú no la tuya de ellos."

We can translate as: "It's easy to like people when they can give their opinion about you, but you can't give yours about them". The right expression of the sentence would be: "Es fácil caerle bien a la gente cuando ellos pueden dar su opinión sobre ti, pero tú no la tuya sobre ellos". Anyway, I think this sentence makes more sense as: "Es más fácil caerle bien a la gente cuando dejas que ellos den su opinión sobre ti, pero tú no das la tuya sobre ellos". ("It's more easy to like people when you let them give their opinion about you, but you don't give yours about them").

It's easy to befriend people when they can give their opinion (talk, gossip) about you, but not the other way around. hope that helps