Get a good book for free, for example PLO THEORY, it is timeless book which ll give you good core concepts of PLO. Alongside invest in Jnandez plotrainer for example which has good training mode and spend daily at least 20min. Also watch some videos and find a study group. Exchanging ideas and talking hands with other humans stimulates also your brain. Play small stakes, dont table select in the beginning. So summing up:
-get a book
-get a some solver
-get a study group or partner to talk
-watch videos
-play, play, play
-rinse and repeat

Most in these forums hate 'play chips' but I say for anyone trying to get the feel for a game it's OK to start there. Keep one of the free Odds/Equity Apps near by and run the hands through just to see how bad the opponents use their chips. You could go to penny online stakes as well, but lots of V on there don't care about chips any more than the group you'll find on play chip tables. I've not played play chip in a long time, but I found once you get into the 'high' stakes play chip tables you actually do run into some pretty tough opponents.

The more you play the more you will recognize spots that make sense to use aggression. Those spots really don't change from play to even $5/5 PLO .. just the value of the chips. GL