In Polish, an "i" palatalizes (softens) the preceding "L" consonant, just as Russian "ю" and "е" palatalize the preceding "л" consonant. So if we would get strictly technical about Polish-to-Russian, then ljubit chljeb would sound incorrectly as лъюбит хлъеб, in which the "л" stays unpalatalized--"hard," hence the hard symbol (твёрдый знак [twiordyj znak]) "ъ."
But, all that aside, your version still makes sense and is easily understood as a Polish transliteration.
In English, however, I wouldn't use "ch" or "j" for transliteration. I would say "On lyubit hlyeb." Since English "L" is never palatalized anyway, the "y" approximates the sound better than an "i", which would sound incorrectly as "лиубит хлиеб". Also, "Х" is most often transliterated as "kh" in English, such as хлеб-khleb or Казахстан-Kazakhstan, but that's confusing to English-speakers because we are inclined to pronounce the "k" and not the "h," that's why I always hear English-speakers saying "Kazakstan," when it should be more closely pronounced "Kazahstan," just with a harder h-sound, like a German "ch", Polish "h" or "ch" or Spanish "j".
False. Polish and Russian languages are both Slavic languages in the first place - they share ancestry. Closely. That's why the most basic words of those two languages are very similar. The words that came much later to Polish as the result of Russian invasions, are called "rusycyzmy" and often frowned upon. And if you want to dig up the history - Poland was the first to invade Russia, up to holding Moscow for a few years in 17th century.
What different words? do you mean conjugation - the way word changer regarding person, tense and gender (think I am, he is, they are)
Ja lubię - I like
Ty lubisz- You (1 person) like
On/ona/ono lubi - he/she/it likes
My lubimy- we like
Wy lubicie - you (all, 2+ people) like
oni/one lubią - they like
here is a table