We already submitted an original research article in a reputed SCI journal on 09/06/2021, and the status has remained “Awaiting Admin Processing” since then. Shall I send a reminder mail to the admin? Is there any wrong with that?
I suggest you give it about a month and then send an email just to inquire what is happening! I have written a paper, viz. “Writing for Publication for Students and University Staff”, which also discusses the review length of time and suggestions of what authors could do. The paper is freely available on ResearchGate: https://www.researchgate.net/publication/342549330_Writing_for_Publication_for_Students_and_University_Staff.
The journal probably may have many papers on the queue, since you submitted on their online platform you may need to give them some more time to process your manuscript. Best of luck!
Regarding status change for submitted journal, you can ask him in writing the status of the paper and there is nothing wrong in it. Editorial office will reply.. Now a days on line check up of the status is possible .