amai mono wo takusan taberu to hutorimasu.

No—Japanese is normally written without spaces:

• 甘い物をたくさん食べると太ります。 Spaces are sometimes added in textbooks or learning materials to help beginners see word boundaries.

甘い物 literally means sweet things / sweet food.

• 甘い = sweet
• 物（もの） = thing(s), stuff
  Using 物 is a natural way to talk generally about a category of things (here, sweets) without naming a specific item.

They mean the same. The difference is writing style:

• 甘いもの (hiragana) is very common in everyday writing.
• 甘い物 (using kanji for 物) is also common and can look a bit more “formal” or “written.” Both are correct.

を marks the direct object of the verb 食べる:

• 甘い物を食べる = to eat sweet things So it tells you what is being eaten.

Here たくさん means a lot / in large amounts and functions like an adverb modifying 食べる:

• たくさん食べる = eat a lot It can sometimes relate to frequency in context, but in this sentence it most naturally means quantity.

Here と is a conditional meaning “if/when (A happens), (B happens)”, often used for:

• general truths
• habitual results
• natural consequences

So 食べると太ります implies a general consequence: If/when you eat a lot of sweet things, you gain weight.

A common way to compare them:

• ～と: automatic/inevitable result, general rule (If you do X, Y happens). Not usually used for requests/commands after it.
• ～たら: “if/when after doing X…” often used for one-time situations and can be followed by requests (If/when you eat it, please…).
• ～なら: “if it’s the case that…” often used for giving advice based on an assumption.

This sentence is stating a general consequence, so ～と fits well.

太ります is the polite present/future form (“gain weight / will gain weight”).
Casual form is:

• 太る (plain)
  So you could also say:
• 甘い物をたくさん食べると太る。 (more casual)

Japanese often omits the subject when it’s understood from context. This sentence is a general statement, so it doesn’t need an explicit subject. In English you might render it as you or people:

• “If you eat a lot of sweets, you gain weight.”
• “If people eat a lot of sweets, they gain weight.”

If you want to specify:

• 私は甘い物をたくさん食べると太ります。 = “If I eat a lot of sweets, I gain weight.”

Yes, it’s grammatical:

• 甘い物をたくさん食べたら太ります。 But the nuance shifts slightly:
• ～たら can sound more like “if/when you end up doing it (in a particular situation)”.
• ～と sounds more like a general, predictable consequence. Both can be used, but ～と feels especially natural for “rule-like” statements.