SketchUp pro 2021 Freezing

Hi All,
I am having trouble with my computer freezing anytime I am working with large SketchUp files.
I am a design builder so am no computer expert and not an architect but us sketchUp for our conceptual designs before sending to a draftsman to create construction drawings. I do use Layout for smaller projects and details for the crew when they are lacking from the IFC drawings.
I have been needing to add more detail lately as I work with clients in the design process.
It seams my files hit a certain size and just stop working. Anytime I try too do anything the rainbow pinwheel kicks in and SketchuUp freezing needing me to force quit. I was running a 2015 MacBook Pro with 8 GB of ram and was told it was the computer.
I recently bought a new Mac mini M1 16Gb ram and 1tera storage. Does the same thing. What am doing wrong?
Any help would be appreciated.

If you consult Model info statistics, how many edges and faces in your model ?

First course of action is determine where the slow down is, Model stats is a good place to start evaluating how heavy the file is. This is available at Window>Model info>Statistics. Knowing the edge count will help to understand if the number of polygons is just so large that it is choking the CPU or GPU. It’s not an exact science as there are other variables but usually under a million edges yields no noticeable slow down and the pinwheel increases as you increase the number of edges SU must calculate. Other notorious slow down are lots of high poly elements brought in from the 3D warehouse, very high resolution custom materials, and complex rendering options like shadows, profiles, or sketchy edge styles. If you can post a model that is slow for you that would be the best way for us to evaluate the problem. It will likely be larger than the forum allows so you will need to use a hosting site like dropbox or Google drive and post the link here.