Suggestion-
Even though you may not have scored so well in school, a report showing that you enrolled in specific courses and earned recognition while doing so would be very helpful in enhancing your profile.

As a Teaching Assistant, you will be-

Helping your professor plan and organize lectures Guiding students with their doubts
But as a Research Assistant helps in researching and conducting new experiments on the field

Here are a few resume writing tips you should keep in mind-

The first and the most important advice I’m going to give you is this – do not exceed a single page. Every bullet point you mention shouldn’t be more and one to one and a half lines. Follow a single chronological order. Use active voice instead of passive voice.

Read this blog to get a proper understanding of how to write a resume for college applications

It's better to have than not to have, you know what I mean?

I think 5 should be enough
Not all colleges ask for official transcripts
And you will need one to send to the university that you get admitted into

Owing to the pandemic, several institutions have started giving a complete or partial college application fee waiver to international students-

University of Bath Kent State University University of Akron Valdosta State University Villa Maria College West Texas A&M University, and more

I suggest you mention co-curricular activities instead of extra-curricular stuff
Your SOP needs to tell the university why they should accept you
So talking about co-curricular activities will be more helpful

You could either send an email requesting the admissions office to waive off your application fee by saying you don't have enough money
Or you could apply to partner universities of iSchoolConnect and get a waiver or a discount on the application fee

You can remove skills, hobbies/interests, or community service

Platforms such as Coursera, EdX, Udemy, etc. offer several certification programs
You can also try Rosetta Stone, Duolingo, and Babble

Use this GPA calculator to convert.

Official transcripts are signed and/or stamped and sealed in an envelope by your college
Unofficial transcripts are not sealed

I suggest you contact your college and inform them about this
They should be able to provide you with an alternative document for this

There are 2 options-

Approach your college registrar
They can directly mail your transcripts to the university for you (you might be asked to fill a form by your college for this) Mail it yourself
Make sure your transcripts are sealed and signed/stamped by your university
And mention the name of your college in the From section of your mail

First, you'll have to scan each sheet.
If your printer allows you to combine these scans into a single folder, do that.
If not, you can combine all of these scans into a single file using an online tool.
There are many options available for this - Merge PDF, iLovePDF, and more.
Make sure the end file is a PDF document.
Then upload it to your application!

Also, if it's not in English, get it translated

10-12 if you're applying at 10 universities

Do not use a tabular format to write about your education qualifications

I suggest you stick to Times New Roman

Not a table, please
Get more details here