Heyo, I'm assuming English isn't your first language? I don't mean that it's particularly bad, but one very common mistake non-native speakers make is using contractions at the end of sentences. It's not 100% universally forbidden, but if you play it safe and make sure your sentences don't end in contractions, you'll avoid the biggest thing that sounds unnatural in your writing at the moment.
("Will you be there tomorrow?" "Yes, I'll." -> "Yes, I will." OR "Yes, I'll be there." etc.)
("Will you be there tomorrow?" "Yes, I'll." -> "Yes, I will." OR "Yes, I'll be there." etc.)