Lowercase Ones Look Like V's Crossword

I'm looking for the name of the case where sentences start with a lowercase letter (so neither sentence case nor title case), but all other capitalization rules are respected. This style seems to be

I tried to google more on the subject, but google never understands my search properly, like "correct way of writing lowercase letter a" So is there a correct way to write lowercase A? Which one is it? Which version do they teach in schools in English countries? What about non-English countries who teach English as a second language?

I use two different versions of lowercase R (often subconsciously) while writing in English for my studies. Is this something unacceptable in cases like exams or assignment submissions?