fFirst

i I am just wondering.

hHow my life iswould change if he loved me?

wWe could achivestay together or we could break up?

nobody can know unfortunately.Unfortunately, nobody knows.

i I’m just wondering.

how my life iswould change if he loved me?

Are you talking hypothetically?

we could achivebe together or we could break up?

nobody can knows unfortunately.

i I’m just wondering.

hHow my life is changes if he loves me?

wWe could achivework out or we could break up?

nNobody can know, unfortunately.

i am just wondering., how my life has changed?

I would say either, "I am wondering" or "I have just been wondering." This is also not a complete sentence and I would have connected the two sentences together.

how my life is change if heDoes he still love me?

When you start a new sentence make sure you use a capital letter. I would also change the sentences to "I am wondering how my life has changed. If he still loves me?"

we cCould achive or wewe stay together or could we break up?

For this sentence I am not sure what you mean 100%, however, for my purposes I am going to assume you mean stay together or break up. If I am correct in my interpretation I would say, "Will we stay together or will we break up?"

Also saying "we could" uses the structure of a statement not a question. In this case you should just switch them around to form a proper question.

nobody can knows, unfortunately.

This is grammatically correct. However, it make the sentence flow better if you put unfortunately at the start with a comma. You could say "Unfortunately, nobody knows." or "Nobody knows, unfortunately."

i I was just wondering.

hHow would my life is change if he loved me?

we could achive or we could break up?

not sure what you are trying to say sorry

i was just wondering.,

how my life iswould change if he loved me?

we cWould achivehave us marry or we could have break up?

I think you meant marrying with „achieving“