Mark Wahlberg is ready to be a grandfather — on screen that is! While promoting his new Apple TV+ film, The Family Plan, the 52-year-old spoke about how he hasn’t been afraid to embrace getting older in real life or on film. “I’m a dad now — embracing my old age. A lot of guys my age in the business would probably say, ‘Well, that character has grown kids or kids in their late teens. I don’t want to play that role.’ I’m embracing that,” the Boston native said. “I look forward to playing a grandfather soon.” While Wahlberg — who shares Ella, 20, Michael, 17, Brendan, 15, and Grace, 13, with wif…