Are Systematic Reviews Efficient To Familiarize Yourself With The State-of-the-Art?
Performing a systematic review is very time consuming. Also, it may result in a &quot;high dispersive work&quot;, if a very specific research question is not set &quot;a priori&quot;.
Also, SR is not only &quot;indexing&quot; evidence, but also effectively aggregating them in a readable and useful summary. If you are not an expert in that field, you may not be able to do that, and the quality of the overall work may be low.
If your goal is to improve your knowledge in a specific field, performing a systematic review may not be the most suitable option in the first place. You'd rather read existing reviews and summary (if any) - this would be extremely more time-effective.
To answer to the other two questions:

Yes, it is possible to do in a matter of weeks, but not entirely on your own (the process of screening requires at least two independent reviewers, according to the PRISMA guidelines).
Yes, if you are not able to reach those literature that meets the inclusion criteria of your SR (and this is quite probable).