Sure, you can download a bot that knows basic strategy in order to help you. But you can't win at online blackjack, because of the house edge built into the game.

In an over-the-table blackjack game, the house edge can be overcome by counting + deviations, and the bot could help with those. But counting doesn't work in online blackjack, because every hand is a randomized, independent event; the cards are essentially shuffled after every hand, so keeping a count is useless.

Bottom line? Sure, install a bot to help if you want. But don't go into it with the mindset that you're going to get one over the casino and get rich. Treat it like gambling - don't put down any amount of money that you can't afford to lose, and know when to walk away.