English to Japanese

Can anyone help me check these sentences from (Eng to Jap) Thanks

この今週はゴールデンウィークですが、皆日本に二三日休みがあります。
(This week is a Golden week and everyone in Japan has a few days off.
もちろん、有名な各地に混んでいる思いいます。
(I think that various famous places will be crowded.)
なので、どこに行ってわからない。
(So, I do not go where to go.)
多分、一日のために原宿の周りを歩いてはいいです。
(Maybe, it is good to have a walk around Harajuku for a day.)

With minimum changes to your Japanese attempts :)

今週は 日本では ゴールデンウィークで、皆 だいたい 何日か 休みます。
(This week is a Golden week and everyone in Japan has a few days off.)
I moved the "in Japan" to the first part of the sentence (because that is where Golden Week occurs), and changed the second to say "just about everyone takes several days off."

有名な 観光地は どこも 混んでいる と 思います。
(I think that various famous places will be crowded.)
"Every famous tourist spots will be crowded I think."
When you want to say "I think that...", you need the と before 思います, like for quoting. "...と　思います"

なので、どこに 行ったら いいか、わからない。
(So, I do not go where to go.)

多分、一日、原宿の あたりを 歩くのが いいでしょう。
(Maybe, it is good to have a walk around Harajuku for a day.)
一日のために was simply too literal coming from "for a day." :)

Thank you for your reply. Just a question, what is the meaning of たらいいか　here ? tara means if?

Yes this たらis the IF expression.
This construction of
どこに行ったらいいか わからない
... literally, if I follow the IF phrasing, means something like:
- I don't know where it would be good if I went...
So "I don't know where I should go."
Similarly:
何を食べたらいいか what I should eat
誰に頼んだらいいか whom I should ask
どの映画を見たらいいか which movie I should watch

all beginners textbook i had looked into till now only had kiku for asking, are kiku and tanomu interchangable when it comes to ask?

Kenshiro,

Maybe I should have used the verb "Kiku/kikimasu" in my example to keep things simpler :)

Kiku/kikimasu - to ask (a question), to listen to (someone, music, etc.)
Tanomu/tanomimasu - to ask or to request (for a favor, to do something for you)