As far as I know, there is only 1 dialect of modern Hebrew, so I don't think that it's related to accent. the reason the "h" isn't pronounced in modern hebrew is elision (when a language loses a sound), it is the same case with the "h" sound in spanish and the "wh" sound in english.
P.S. I should've also explained it better, it's not that you can't pronounce the "h" sound, it's that it's optional in Hebrew, and most native speakers don't pronounce it, except maybe in careful speech.
Well, what's the distinction in English? That depends on context.
If it's about a food or a song, AFAIU "love" is the same as "like" except stronger. In Hebrew we'll probably use "אוהב", and if needed add an adverb to mark if it's strongly or weekly or very strongly or whatnot.
When it's about a person, sometimes "love" would mean a categorically different emotion than "like" (e.g romantic love, or parent-child love, vs. general positive attitude). Hebrew would again tend to use "אוהב" anyway, but if we want to stress that we just like another person and not love them, we'll might use the verb "מחבב" (mechabev). It used to be a very literary and outdated word, until a few decades ago it was resurrected specifically for this purpose.
Hebrew has 4 letters with 'sofit' forms or 'final' forms. when that letter ends a word, then the sofit form of the letter is used. you can look them up if u want, or just learn them as this course introduces them. but just to give you that tip ('heads up'), there are 3 other letters that do the same. the 'n' (nun) has a sofit form too. i don't remember what the other two are 'off the top of my head' (that i can recall at the moment without consulting a reference myself).
eK, the alphabet was introduced in the tips and notes section before the first lesson, but if you don’t have access to that, cartoonhebrew.com is a good site for remembering the letters.
When Duolingo introduces a new word, it highlights the new word in orange, and to know the meaning you can go to the Pealim site which is very good in giving you singular and plural, conjugations etc.
Good luck! בהצלחה Behats’lekha!