Free user limitations - inserting rows and columns, and customising columns

Hi there smartsheet community! New poster here :)

I'm needing to know more about the limitations of free user accounts. Specifically I'm wondering if free users are able to insert rows, or customise/insert columns into sheets that are shared with them. I've looked everywhere, and although there's great general advice and a video on the website, I can't find the answers I'm looking for. I'm assuming free users can't do these things but need to be sure.

I'm hoping someone here can help me get to the bottom of this, I'd really appreciate it.