Is It Realistically (Thinking) Start a Acting Career At 21Yr?

because i've always wanted to do acting but i have ADHD, & anxiety problems while growing up as a school & i wasn't really Motivated either like i did Acting for my church when i was 13yr & it felt corny a bit...& i did a skit...& i remember it but it was about Teens When there Peer-pressured to drink & i had to act as if i was about to drink it....& a angle frozen every body but me & she was talking to told me & she said don't do it your to cool for it Say No To Drugs & Alcohol..& then after the angle says that time unfroze & i tell them naw im straight....im to cool & i find it ironic that thru most of my teen years like i always ended up doin something with Acting like nothing major though...& my 3 choices were when i wanted to finish high school was i was gonna either be a carpenter, Actor, Photographer..but yea soo i really have no Acting background....& some times when i talk to my mom over the phone she'll say where did acting come from & i told her i really care about the fame...but acting is fun & im thinkin about goin to school for it & she was not down with it she said u have no acting background u need a job ur living in a Apartment with really no money....she still wants me to go to a School like everest or something but yea