Separating and combining meshes

Hello,

I’m quite new to Blender, but I’m interested in learning it. You can expect to see me asking many questions in the near future about the specific issues that come up while I am trying to find a foothold in the world of modeling.

One of the first issues that came up is that I need to detach a piece from my mesh and treat it as a separate mesh. Does anyone know of a way to do this? And while we’re at it, how would you do the opposite: if you have two separate meshes, how would you combine them into one?

Thanks in advance for the help.

In edit mode select the vertices you want to be separated,press P key, and crtl+J
after selecting the vertices to merge…

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