In general, your question suggests that you need to do a lot more reading. It sounds like you need an adviser who knows at least the basics about personality measurement. Perhaps you need to collaborate with a personality researcher.
If you simply want to administer a personality test and provide feedback to participants, this is fairly straightforward for a personality researcher.
There are a wide range of personality tools that are in the public domain.
You could look, for example, at some of the measures listed on the IPIP website: https://ipip.ori.org/newMultipleconstructs.htm
If you look up the literature on these measures, you might be able to get some basic norms that could inform feedback. Equally, after you have administered a particular test to participants you could develop local norms used to inform feedback.
You could also take a few online measures that provide feedback to get a few ideas: