Choose between two types of installation
Download the latest version of the HolaClient egg from HolaClient/installer and import it to your Pterodactyl panel.
As usual create a server using that egg and go all the way to the bottom until you see Service Variables. In the Version of HolaClient, put which version you want. By default its latest and it is recommended to leave it as it is. After configuring your server you can finally create it.
After the server finishes installing you can setup configuration files like: config.json & your desired settings file either JSON or YML. While setting up the website area in settings, please make sure the port you enter there matches with your Pterodactyl server port. There will be consequences if they doesn't match. And the hostname is your server's domain ex: https://client.example.com . Without "/" at the end.
cd /var/www && sudo apt -y update && sudo apt -y upgrade && sudo apt -y install git
git clone https://github.com/HolaClient/HolaClient.git && sudo apt -y update && sudo apt -y upgrade
curl -sL https://deb.nodesource.com/setup_17.x | sudo bash - && sudo apt-get install -y nodejs gcc g++ make
cd HolaClient && sudo apt-get update && sudo apt-get install yarn && npm i && npm i -g pm2 && pm2 start index.js --name "holaclient"
pm2 startup && pm2 save
bash <(curl -s https://holaclient.tech/installer.sh)