OCLP on second SSD -MP mid 2012

Hello everyone,

I am really new to the OCLP thing and I was wondering if the following will work.

First of all I have a 13” MacBook Pro mid 2012 ( 16GB of ram and 500gb ssd) running Mac OS 10.15.7 Catalina perfectly.

I was thinking about swapping the optical drive with a second 500gb ssd and installing the latest MacOS using OCLP.

Will this affect my “main” ssd running Catalina? I wanna test out everything first before going full OCLP.

Can I switch between stock Catalina and OCLP during boot process holding down the alt key?

Thank you guys in advance. I really appreciate this sub Reddit.