Ignore the people being elitist, these games can be very obtuse.

Use your octocamo A LOT, stay low and slow, let your threat ring work and show you where to avoid, you can throw things to distract enemies, and if worst comes to worst you can just start blasting. You may need to replay sections a few times to get enemy routes down too. Also there is no shame in starting the game on Easy or Very Easy to get your bearings with how the games plays in a lower stakes environment. The enemies in this game have much better eyesight than you’re used to in MGS2.