Recently I bought a MacBook Pro (Apr 2020) with only 2 ports (Mini USB?). How do I connect my HP 27es monitor?

Determine the connection that monitor requires, and then read Use an external display with your MacBook Pro - Apple Support to determine the cable you need.

The manual for that monitor is here: https://support.hp.com/us-en/product/hp-value-27-inch-displays/3989902/model/10402870/how-to

the manual says

1x Analog VGA (do not use that!)

and 2x HDMI

buy the Apple USB-C Digital AV Multiport Adapter and you can plug in the power adapter into the provided Charge port (same shape as USB-C port on the computer). It also provides a traditional USB port, connector is USB-A (rectangular) speed is USB-3

https://www.apple.com/shop/product/MUF82AM/A/usb-c-digital-av-multiport-adapter