AThe Fall Semester Has Started

Having said that, most of the classes art my university are going to be held online, so I will stay at home all day.

I took classes 'm taking Quantum Mechanics, Thermodynamics, and Drafting.

Getting rid of "classes in" makes this sentence more concise.

In these classes, I most favor Draftinglove Drafting the most because it seems exciting and I like to domake fine works.

However, unfortunately, I can't use a drafting room, so I should unfortunately, so I plan to draw blueprints on my small desk.

It wouldis going to be troublesome and frustrating.

Tomorrow is also a full day of classes for me, but I'm looking forward to taking new classes and gaining knowledge.

AThe Fall Semester Has Started

Today wais the first day of the fall semester.

I took classes in Quantum Mechanics, Thermodynamics, and Drafting.

just to clarify what you mean by this sentence - are you saying you are currently taking these classes, or you previously took these classes? If the latter, you would say "I am taking ...". If the latter, I would say "I took classes in ...... in the past/in previous semesters." This way, your message is more precise.

InOut of these classes, I most favoprefer Drafting the most because it seemwas exciting and I like to doenjoyed doing fine works.

I am assuming that these classes were taken by you in the past. If that is not the case, you can keep the verb tense in the present. Also, I do not understand what is meant by "fine works".

However, uUnfortunately, I can't use a drafting room, so I should right at school right now, so I will need to draw blueprints on my small desk.

Using "however" and "unfortunately" is redundant.

It wouldill be troublesome and frustrating.

Tomorrow is also another full day of classes, but I'm looking forward to taking new classes and gaining knowledge.

See you.

It is not necessary to say "see you". First of all, you are really not going to "see" anyone, secondly, it makes your essay too informal, lastly, you're not writing a letter, an email or a text, therefore, you do not need to use a "complementary closing".

AThe Fall Semester Has Started

I took'm taking classes in Quantum Mechanics, Thermodynamics, and Drafting.

In these classes, I most favor Draftinglike drafting the most because it seems exciting and I like to do fine works.

I'm not sure what you mean by 'fine works'. If you mean detailed work, you can say "I like doing detailed work".

However, unfortunately, I can't use athe drafting room, so I shouldhave to draw blueprints on my small desk.

It wouldis troublesome and frustrating.

Tomorrow is alsoI also have a full day of classes tomorrow, but I'm looking forward to taking new classones and gaining knowledge.