Hello. Single (again) 40 year old Male, going to be forced back to the dating world now that my (Ex) wife is gone.

From my younger days I remember the supposed formula of "Half your age, then add 7" which would put me at the youngest person I should date (without being too weird) would be 27 years old. Does that seem correct, in your opinion(s)? -I would not want to/ and should not date anyone under 30 years old and it would probably be better closer to my age than 30.-

To add, I have no kids, but would like to, and I know it is usually more rough on women for pregnancy at a later age. I want to clarify I have no issue dating my age and/or even older (My partner before my wife was significantly older than me) -Ignore this.-

I just want to make sure, since I have absolutely no clue what I am going to do anyway, that when and if I do "shoot my shot" at someone, that they wouldn't be wary about my age or the age difference. I have no idea where to even start these days, but still I need the advice.

Thank you in advance.

-I edited the post after some responses to clarify if there were any further responses. The edits are in bold and one part strike through.