I found and applied for a job through LinkedIn, so I feel it should be reputable, but I have heard that is not always the case. I was asked to apply through their page and told I was shortlisted for the next phase. The position offers $65K annually, full-time. Does this sound legitimate?
I once found a job on LinkedIn that seemed perfect, and after applying, I was excited to hear that I was shortlisted quickly, just like you. The position offered a decent salary, and everything looked legit, especially since it was through LinkedIn. However, I’ve learned that not all jobs posted there are as reputable as they seem. It’s great that you applied through their official page, but I’d recommend doing some extra research on the company—check reviews, their LinkedIn profile, and even reach out to current or past employees if possible. Sometimes, a quick offer can be a red flag, so make sure everything checks out before moving forward.
Hire Standards Staffing appears to be a legitimate staffing agency. They focus on connecting candidates with job opportunities in various industries, including administrative, finance, and IT
First of all, congratulations on being selected for Hire Standards Staffing’s next round of the process! 
Although LinkedIn is a reliable resource for job seekers, it’s always a good idea to double check your information. To gain an impression of a firm’s reputation, you might go through Glassdoor reviews and company ratings.