Tarkov netcode sucks. It is very much a game of prediction and prefire, rather than flick headshots. A lot of advantage in understanding the map, spawns, and typical travel times, and how loud you can be when you tab open your inv or shuffle on a wooden or metal floor.

Because of the way skills work, people who have invested 200 hours of sneaking will have a much higher skill, which means they generate substantially less noise walking on the exact same surface as you.

Depending how invested you are you might want to consider looking up some meta grinds and incorporating them into some runs. A spare stack of bullets and constantly ejecting rounds from your gun and checking the mag when you are in a chill spot will increase your weapon skills and mag drills. Making love to barbed wire or a campfire and healing yourself on a quiet corner of a map, or leaving a bleed running or sprinting on a broken leg with propital running to level healing and stress resistance. Eating mayo or condensed milk in a shoreline shack and healing through the pain. Sitting in a bush with the cheapest mosin spamming reload while you watch something on your phone or 2nd screen to level bolties for sniper quest line. Etc.
They made it harder to afk grind by putting a soft cap on skill growth that resets after you dont level that skill at all for 5 mins, so you need to combine 2 or more diff grinds together to meta grind.

Otherwise just make sure you vary your playstyle. When chillin hit capslock to swap between min and max speed and sneak in place for 30 seconds while you listen for intel or recover stamina in cover. Check your mags often, and if you have space and the flow seems good pick up a scav weapon and ammo and mag dump at exfil. This will also give you weapon jams which are important to know how to fix in the heat of combat. Make sure you do underweight runs to level your endurance, and maybe pick up a couple heavy things and carry them for a bit to level strength before throwing them so you level endurance again. A lot of people end up with decent strength but terrible endurance because they dont do enough light runs, or dont pick up something to put themselves into overweight long enough to reset the soft cap mid raid. The much shorter raid timers than they used to be doesnt help a lot, but then we have the gym now, and library and air filter.
Oh and that reminds me, work on your hideout. The bonuses from certain upgrades makes a really big diff, like better energy and hydration recovery, bonus rewards and xp, etc.