OPT F1 Tax filing status

I completed my Ph.D. in May 2019. I was an international student on F1 Visa. Now, I have OPT and I am teaching at a University. I have two questions: 

Q1) Would I be considered Resident Alien for tax purposes? I did not leave the country in 2018, 2019 and 2020. And my OPT started on July 15, 2019. And F1 visa was started in April 2015. 

Q2) Now I am on OPT F1, what is my tax filing status? Would I have to file tax online or send the papers physically? I have two W2 forms and one NC W2. I also have a Tax treaty document. Which Turbo tax product is best for me. Thanks.