I don’t know what you mean by “install” bs4 in Sublime Text. Sublime Text is an editor. There is now bs4 package in packagecontrol: https://packagecontrol.io/search/bs4. Are you trying to write a Sublime Text plugin? Are you trying to install beautifulsoup on your computer and write a normal script with Sublime Text?
Either way, Sublime Text questions should probably be asked over at their forum: https://forum.sublimetext.com/ or their discord channel: https://discord.sublimetext.io/.