AMD Vega 8 to GTX 1650 in Acer Nitro 5

[PUNISHERoooo]

Im new to this forum, I dont know whether im right or wrong and im not a tech guy..

My laptop specification is;
Acer Nitro 5 AN515-43
AMD Ryzen 5 3550H Processor (Vega 8 Graphics)
Nvidia GeForce GTX 1650 Graphics
8GB RAM

I bought this laptop on October 2020. Before playing games, I already configured the settings in Nvidia Control Panel and also in Windows Graphics Settings to use GTX 1650 in high performance. If I start to play Valorant(other games too), I'll get 100 fps but after sometimes it will drop to 20 fps and even lesser to 4 fps at CPU temp at 96 C; GPU temp at 70 C. I never ran any other programs while playing. I came to know that, in Task Manager it is showing "GPU 0: Nvidia GTX and GPU 1: AMD Radeon". Is there a way to change? Ive also tried changing the global settings in high-performance Nvidia processor and also changed in program settings to high performance. 
Is there a way to put my dedicated GPU to GPU 1? and how to get stable fps? Or is it okay to keep as it is?
Is there a way, so i can play better...
In YouTube videos benchmarks, i can see that their laptop temp just stays at 86C with stable fps...

And also you can see that my laptop is only using 6GB RAM, where i got 8GB installed. Is there a way to make my laptop to use 8 GB of RAM?

Thank you  ...

[PUNISHERoooo]

3 minutes ago, Benji said:

To my knowledge, it'll always list the dGPU as the GPU 0 and the iGPU as GPU 1. My stepmom's laptop does the same thing IIRC. But the order in which they're listed in the Task Manager doesn't matter anyway, once you set the dGPU to be processing the games, it'll do just that.

The RAM is going to the iGPU for it's "dedicated" VRAM and other hardware. There's nothing you can do about that because most laptops don't allow you to change the amount of fixed VRAM it dedicates to the iGPU.

Oh, thank you... So ive got 8GB ram, but it is showing only 6GB of 8GB in usage... is that okay?

[Mnky313]

7 minutes ago, PUNISHERoooo said:

Oh, thank you... So ive got 8GB ram, but it is showing only 6GB of 8GB in usage... is that okay?

It's probably reserving 2GB for the iGPU's vRAM. There might be a setting in AMD's control center thing or the BIOS to adjust the amount it's reserving.

[PUNISHERoooo]

51 minutes ago, Benji said:

Yes, it is. It does that because the "dedicated" VRAM of the iGPU and other hardware using RAM in a "dedicated" way don't show the RAM in the RAM tab. My laptop, for example, has a cache-less NVMe SSD and dedicates 256MB fixed to the iGPU. It ends up showing 7.6GB or 15.6GB as available, based on whether you assume the original 8GB or my upgraded 16GB. If you look up in the system info, it'll show 8GB installed (5.9GB usable) or something along those lines.

Oh okay, if it is okay, then no problem. I dont have that much knowledge in computer hardware

[PUNISHERoooo]

and also, can you help me in this. I played Valorant for 45 min(now) Why it is getting so hot? and why more cpu usage than gpu?
I used to keep a object under the laptop, giving it a rise from the table. What am i going wrong?

Is there anything to do in power management? I keep high performance(by default my laptop had only balance, power saver and Acer Balance) I'll select high performance from the NitroSense