1. Install Ruby
I choose "Ruby+Devkit 3.2.11-1 (x64)" since it matched my jekyll version
Once downloaded install everything from MSYS2 development toolchain

2. Verify everthing is good in command prompt
ruby -v
gem -v
bundle -v

3. Create a gemfile if it doesn't exist (no extension)
source "https://rubygems.org"

gem "github-pages", group: :jekyll_plugins
gem "jekyll-remote-theme"

4. Install jekyll
bundle install

5. Once everything works start local server
cd C:\Users\apuid\Documents\GitHub\Portfolio
bundle exec jekyll serve

http://127.0.0.1:4000

Note: This hasn't been tested apart from my personal workstation and some file path won't match your needs.