Where Do Students Check Writing Mistakes Before Submitting Important Assignments

This week at university, I was busy finishing a long research assignment while also preparing for class presentations. I wrote the paper late at night and later realized I might have grammar and structure mistakes that could affect my grade. While searching for simple student tools, I noticed many people talking about Tea Checkerapp for reviewing academic writing before submission. It made me curious because students often need quick ways to check their work when deadlines are close. Has anyone here used Tea Checkerapp to review assignments and does it really help improve writing quality before turning work in?