Niche Weight Loss in French

I would like to have your feedback on my niche:
I like to help French speaking executive women between 25 and 35 years old to lose between 5 and 10 kg for good. Thanks to my program called “Coaching Énergie”, their weight and diet will never be a problem for them again.

Is this specific enough?

If not, I was thinking that I should also target women who are in the legal or financial fields in Luxembourg. But I asked my employer to authorize me to declare myself as a self-employed entrepreneur in addition to my job as a legal counsel and I still haven’t received the answer. I’m afraid that if I mark too much in Luxembourg, I’ll be at odds with my employer.

I also wanted to know: once I have my niche: am I supposed to write it clearly on my Instagram and website or can I use it only for the way I write my content and offers ?

Thank you in advance for your feedback!