What's the difference between the endings "-eba, -ra, and "?

Question:

I mean, what's the difference between saying: あれば、あったら and あると。(When using the verb "Aru".)

By the way, Please correct this sentece I wrote in japanese and explain to me why it is right or why is it wrong, so I can understand the difference.

What I want to say is " Even if they are a lot of otakus in Japan, a lot of people believe that if you play videogames you become stupid."
日本では沢山のおたくがいても、
ゲームをすると馬鹿になると信じる人達も多い。

Please tell me if I my sentence is right and explain if I should say ゲームをすれば or
ゲームをしたら. But to me ゲームをすると sounds better,

Thanks.

Answer:

a. 夢（or お金）があれば
b. 夢（お金）があったら
c. 夢（お金）があると

To me, there's not much difference in 3. (they're all "conditional")
I can't choose one that sounds "the most unlikely thing that can happen."


日本では沢山のおたくがいても、
ゲームをすると馬鹿になると信じる人達も多い。

Japanese 馬鹿 is a really tricky word. In your context, 馬鹿 could mean "mania" "freak" "someone who's not intellectual", "indifferent person", which is not as insulting as "stupid" or "an idiot"

女に「美人だ」とお世辞を言えば、女はたちまちばかになる。(proverb)
Tell a woman she is fair, and she will soon turn fool.
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ゲームをすれば and ゲームをしたら sounds more "conditional" (talking about people who don't really play v-games and it means "IF they PLAYED")
ゲームをすると sounds both "conditional (IF they PLAY)" and "when they play...."

For your Japanese sentense, it'd be more natural to say
日本にはオタクとよばれる人がけっこういますが、
あまりゲームばかりしていると、”頭が変になる(= go nuts)” と思う人も多い。
（It's talking about people who actually do play v-games, but IF they play TOO MUCH）
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