This is definitely achievable. If you're 4-tabling 10NL 6-max zoom NLHE on PokerStars
, you can smash through 1k hands per hour, and if you're a decent player, a win rate of 5bb/100 is definitely attainable. This equates to $5/hour in net winnings, not taking into account bonuses and rakeback. So if you do this for 2-3 hours a day, 30 days a month, then you'll achieve your goal.
Here is the catch though: just because your average hourly win rate is $5/hour, doesn't mean you'll simply earn $5 every hour. You'll have upswings and downswings as large as 10 BI at this stake. So you could play a 3 hour session and actually lose $100, even though you were expecting to win $15. For this reason, you'll want at least a 30 BI minimum bankroll (so $300+ in your PokerStars account).
The other catch is that this assumes you're a decent player who can beat micro stakes online poker. Don't expect to just dive straight into this and immediately have a positive win rate. The games are tough nowadays and it takes a lot of practice to reach this level.