I have just started my Fungi journey last year and I have been done a lot of research around it.
What kind of
mushrooms do you want to grow? Plug mushrooms do best in fresh cut
wood before other mushroom mycellium can take a foothold.
I do not use dowel plugs, I use sawdust spawn with good success.
You want a 5/16 bit and to drill 1 1/4" holes about every 5". It is messy and tedious but with some patience and some kind of tool like a screwdriver you can pack them in.
I got some Box Elder logs that are cooking with some oyster mushrooms, and I have collected some 'wild' gold oyster logs that keep flushing like no business.
I now prefer mushrooms that grow in a bed style with mulch, mostly Wood Blewits and Winecaps at the moment. I'm still trying to get my identification game down.