I'm a freshman in university student.

We can't go to the university anymore (because of COVID-19).

I have to study for using PCuse my computer to do my homework, but I'm not good at using PCthe computer.

I have to open my PCturn on my computer every day because I need to check indicfor information from my university.

It is difficult for me to answer the questions.

Whenever I see the look at my emails, I wasbecome afraid and sad.

When we can goBy the time we can return to our university, I wishhope my English skill iss can level up!

I want to study English hard until finishthe end of the coronavirus situation.

Of course, I will study until I can speak English fluently.

I want to study English hard until finish coronavirusthe end of the pandemic.

More natural to say "I want to study English properly until this whole pandemic is over."

Of course, until I speak EnglishAnd after obviously, until I'm fluently.

Add obviously to sound more natural. Of course is fine as well though. You don't need to repeat "English" because it's assumed that's what you're talking about.

I'm a freshman at university. / I'm a first-year university student.

What you wrote is okay, but I changed it to sound a bit more natural. You could use either of the options I gave you.

I have to study for usinguse my PC to do my homework, but I'm not good at using PCit.

I have to open my PC every day because I need to check indnotifications from my university.

"Open" is fine if it's a laptop computer. If it's a desktop computer, then "turn on" or "use" is more appropriate.

It is difficult for me to answer the questions.

Whenever I see the check my emails, I wasfeel afraid and sad.

When we caI hope my English will level up before we return gto university, I wish my English skill is level up!. / I hope I can level up my English before we return to university.

I want to study English hard until finishthe end of the coronavirus.

Of course, until II want to speak English fluently.