Dear Nene,
nice to meet you, my name is D, i am a newbie here too. :p
we have one more thing in common, let's cheer for the love of English
A new semester is a new beginning, you'll be fine as long as you have the heart for it
i don't feel comfortable with your sentences, i hope you don't mind if i made some suggestions
"This semester i must progress"
i kind of understand your underline point, but it just doesn't sound right to me
how about " I have to (must) make some progress in this semester"
"Let us together," this is only half of the sentence
how about "Let us work hard together" or "Let us do this together"?