Ya, surely you can pursue B.Tech at the age of 28 as learning has no age bar and age is just a learn. If you have zeal in you then you can do anything you want at any point in your life. Ya, it will be hard because of the society and many other reasons that will make your path a little bit harsh but if you have a great determination power you can surely achieve that. So, all the best and don’t be afraid of anything because difficult path usually leads to a beautiful destination.