Part 2, please read part 1 first.

1/ "Bed" = letto, "bad" = brutto.

2/ When you are talking about the state of repair of a building (or the health of a person), "condition" is usually singular since it refers to the overall state of a person's health or a building's upkeep. "The athlete is in good condition, but the gymnasium is in bad condition".

3/ "Pavement" is usually singular but I haven't changed that because it would be plural if it referred to (for example) the two pavements that might run on either side of the building. However it's worth noting that "pavements" are usually not part of a building, but rather the street outside of a building. You may have meant "driveway" (the paved path for vehicles leading from the road up to the building) or walkway (the paved path for people to walk up to the building.)

-It is raining a lot.If you don't take an umbrella,you will get wet.

"You get wet if you walk in the rain". This is just a statement of fact; it refers to something that has no time associated with it. It could be past, present or future. However:

"You will get wet if you walk in the rain". The "will" moves this into a conditional future tense. It will happen in the future if you don't take an umbrella.

-If Janice didn't cook so well,I wouldn't eat so much.

That one is fine as well.

My English exam is in a week! OMG

First, in bocca al lupo. Second, remember that in English, language and country names are always capitalised.

Grammatically that's fine, though the content is questionable. Her ceasing to cry won't give you any insight into what her problem is, though you will perhaps be able to ask her to explain what her problem is.

-My cat will lose weight if she don't doesn't eat any pasta.

Of course you'll probably end up with an annoyed cat in my experience. "Do" is one of the harder verbs to conjugate in English but like "Fare" it's one of the most important ones so you need to know it. Remember that it's I don't, you don't, he doesn't, she doesn't, they don't. So "doesn't" is always used for the third person singular. (Or in this case third cat singular.) In every other case it's "don't".

-If my clients arrive tonight, Mattew Matthew will take them out for dinner.

That's fine. And I'd like to go to a pasta place.  Tell Matthew my cat will be coming with us.

-If we go there by car,we will arrive earlier than we expected.

That's also fine.

-If you send me an sms SMS I'll reply to you.

1/ Initialisms (words which are made up of the initials of other words like SMS or FBI) are usually typed in capitals in English.

2/ "Reply", when used as a verb with an object (in this case "you") after it, can never stand by itself. It is always "reply to" whoever. You could however omit "you" entirely; "If you send me an SMS, I'll reply" is also correct.

-If we don't conserve energy, it will turn off in an hour.

There's nothing grammatically wrong with the sentence but the content is a bit of an issue. "Turning off" usually implies that someone has chosen to flip a switch to cut off the power. However that doesn't seem to work with the first half of the sentence; turning something off usually doesn't have anything to do with the question of whether or not you conserve it. If this is a situation where, for example, a backup generator with a limited amount of fuel is in use, it would be more likely expressed as "If we don't conserve power, it will run out in an hour." ("Power" would normally be used rather than "energy" when referring to an electricity supply but that's not important. The important part is the distinction between "run out" (as in, there won't be any more of it) and "turn off" (there is more of it, but someone has just chosen to disable the flow of it.)

-The water evaporates if it boils.

That's fine.
-If the thief hadn't closed the door so noisly noisily , none would have heard him.

"None would have heard him" is OK, but it's a bit literary. It would be more common to say "no one would have heard him", as in "no person". Argh, out of space again...

My english exam is in a week! OMG