If time is an issue, I would learn the 5-min ORB. Carlos taught a very good class on it. Here's the link
https://bearbulltraders.com/course/strategy/lesson/abcds-orbs-2/topic/trading-a-5-minute-orb-2/
In my opinion, the 1-min ORB is too dangerous for beginners, the 5 min can be fast too, but very effective when practiced and having a strong foundation on how everything else works. I tossed my other strategies, and strictly trade 5 min ORBS. I wish I would of started with them since the beginning. I've been having a high success rate with it. Good Luck on what you decide to do.