64 Emulator on raspberry pi 5

So I'm new to both Linux and raspberry pi. I got this whole project I'm trying to do but to start off I'm trying to get an n64 emulator without using retropie as i still want to be able to access other programs. i was able to install retroarch but cant figure out how to install the cores. I'm running into some issues trying to get mupen64plus installed, it just doesn't seem to install for whatever reason. i tried following the guide on the github

git clone https://github.com/ricrpi/mupen64plus
cd mupen64plus
./build.sh
sudo ./install.sh

and even this one that i found

cd ~
sudo apt install libboost-dev
sudo apt install libboost-filesystem-dev
wget https://github.com/mupen64plus/mupen64plus-core/releases/download/2.5.9/mupen64plus-bundle-src-2.5.9.tar.gz
tar -zxf mupen64plus-bundle-src-2.5.9.tar.gz 
cd mupen64plus-bundle-src-2.5.9/
sudo CFLAGS='-mfpu=neon -mtune=cortex-a72 -march=armv8-a' ./m64p_build.sh NEON=1 USE_GLES=1 VFP_HARD=1 NEW_DYNAREC=1

but it kept saying no directory found when i did

cd mupen64plus-bundle-src-2.5.9/

does anyone have a step by step "explain it to me like I'm 5" guide to getting one installed? or a simple way to install mupen that someone who has never used Linux can do? or am i just doing something incorrectly?

check using dir in the terminal, the folder name could be changed

so it hasn't been renamed at all, at least not that i can tell

what does it mean by "please re-run build.sh" if i do it a second time it just comes back with the same response