- Most hétvégén = ezen a hétvégén = this weekend
- Most hétfőn = ezen a hétfőn = this Monday (works the same way with other days)
- Most vasárnap (no suffix here, because there has to be an exception) = ezen a vasárnapon (the suffix returns) = this Sunday
- Most októberben = this October (I have never heard "ebben az októberben"; the same with other months)
You can't use most with the words "hét", "hónap", "év", etc.
- ezen a héten = this week
- ebben a hónapban = this month
- ebben az évben = this year
The thing with "most" here is that it refers to the future. The next occurrence. Or sometimes the recent past. But not the present. So, you can't use it for the week that is already in progress.
(Maybe I need to re-think this. We can be in the Summer and we could say "most nyáron". Or "most októberben", while we are in "October". So it is possible with these longer periods of time. But not with week/month/year.)
And "hét", "hónap", "év", maybe they are too generic? I don't know.
But you can use "most" with seasons.
- Most nyáron - this (coming or recently past) Summer
And for those where you can't use it, you can include one more word, and it becomes OK:
- Most következő héten
"Következő" means "following", "upcoming", that sort of thing.
And a side note on "next". It translates to "jövő" in Hungarian. ("Jövő" as a noun means "future"). So, you can say "jövő vasárnap", "jövő héten", "jövő októberben", etc.
But if you set up a meeting/date for "next Saturday", "jövő szombaton", make sure to clarify which Saturday you are talking about.
You may be thinking of this upcoming, very next, Saturday at the end of this week.
And your Hungarian counterpart may be thinking of the Saturday at the end of next week!
So, just double-check!