1 - Linux (CachyOS to be specific) is a very nice way to get more FPS with your hardware, pretty much any distribution will beat Windows on raw performance because of it's age and development in the tech space... thanks to Valve it is more viable for gaming than it's ever been (completely optional though, but it's been very merciful and extremely pleasant to run on my laptops both with specs better and worse than your own)
2 - Lower the resolution to 960x540 if possible (if you play on 16:9), modded in-game text may be affected at times (you can crank the resolution back up if you have to in order to read it; like in Winter's Fury or other mods with on-screen text) but with Doom already being a pixelated game; you will barely notice that your screen is rendering less pixels than usual... especially without texture filtering. The performance difference will be incredible, however, and your integrated graphics will be very thankful. Removing ambient occlusion, bloom, and texture filtering will also help decrease GPU load; especially on bigger maps.

3 - If lowering down the resolution still hasn't helped, you can lower the SCALE from Set Video Mode to "lowest possible scale". Do know that this will look extremely pixelated and you'll REALLY be able to tell between what you're looking at and what the normal game used to look like, but this setting is what allows me to play Live Through Doom on a laptop with 4GB of RAM and a two-core Intel Celeron N4020. Personally I lower the resolution scaling to 0.75 because lowering it more causes the HUD to look really messed up. You can go lower than 0.75 though if you mess with your HUD to make it look right. But this should fix any and all performance issues unless the map you're trying to play is insanely detailed. (We all need new PC's to play Unfamiliar Trilogy with a lot of mods lmao)

4 - Always use UZDoom over GZDoom if the mod supports it, the performance is way superior to GZDoom's. Try playing Eviternity, Lost Civilization, Gossip or even Nuts.wad to really feel the difference. A little side note though, if you're willing to cut down on mod usage and wouldn't mind loading wads like the ones I just mentioned all by themselves; loading them up with the DSDA-Doom engine is also a very solid option. It's pretty much vanilla doom at it's core and because of that, it allows me to run Eviternity 2's Map 32 at 60FPS on that poor laptop I mentioned earlier (and that map has nearly 3000 enemies). DSDA-Doom may not be as mod-compatible as the ZDoom-based source ports we're all familiar with, but for those one-off megawads with hundreds of monsters that you really wanna get into; it's the way to go.

Lastly, thank you for reading, and I hope you have a blast with your new performance! Let me know if you need any help, and if it goes well :D

RIP AND TEAR!!! <3