What a thesis is
A thesis is your answer to the question in one or two sentences. It is not the topic, and it is not “This essay will discuss…”
Weak → stronger
Weak: Social media affects mental health.
Stronger: While social media can support peer connection, its design incentives make heavy use more likely to increase anxiety among adolescents than to reduce it.
Weak: There are advantages and disadvantages of remote learning.
Stronger: Remote learning expands access for working students, but without structured interaction it weakens formative feedback — so hybrid models are usually stronger for undergraduate courses.
Test your thesis
Ask: Would a thoughtful person disagree? If not, it is probably too vague.