Watch this video first. It shows you the main point in configuring PUBG. Thanks, WackyJacky101!
The key takeaway is FPS, FPS, FPS! Even top streamers and pro gamers don´t own systems that can provide maximum FPS if all settings are on “ultra”. Undoubted settings for Shadows, Effects and Foliage should be “very low” or “low”. Any higher setting won´t change much but costs many FPS.
This guide gives you a deeper inside into each setting: https://www.eurogamer.net/articles/2018-12-07-pubg-graphics-settings-how-to-increase-fps-best-pubg-settings-5414
Anti-Aliasing costs not so many FPS even on “high” or “ultra”, so if you can´t spot enemies on “very low”, try a higher setting.
Post-Processing is not needed any more because of the switch for “sharpen”. Turn “sharpen” on and set PP to “very low”.
Textures are a matter of taste. Higher textures look shiny but have side effects like dirt on the windows.
View Distance is also a matter of personal taste. It determines in which range objects are rendered and get textures. Player objects get always rendered, but at “very low” it is possible that you can see an enemy although an unrendered rock or a tree exists in your line of sight. This can be an advantage (hey, I know you are there) or a disadvantage (Hm? I shot and the bullet didn´t reach my target. Did I reveal my position for nothing?). “Medium” is a good mix and helps to see more objects while parachuting.
What else do we have? Always play in “Fullscreen” mode and as WackyJacky101 stated in his video, set the resolution to native full HD 1920 x 1080. If your system is a beast and has the capability to perform well with a higher screen scale, then raise it to the maximum. Higher screen scale renders the frame with a higher resolution for a smoother image.
V-Sync and Motion Blur should be turned off in any case. Both settings can cause high input lag.
Last but not least – Camera FOV. Again a setting you have to find for yourself. Many players set it to “103” to have the widest angle to spot enemies. Many play around “90”. If you jump and turn to your sides while moving, normally you will spot enemies around you. Low-end-systems perform better with “80”. With “80” the game appears to be very slow. Some Streamers play with “85” or “95” – you see, it´s all about personal preference. One rule: More FOV = less FPS.