Pd 0.46.7 and ubuntu 16.04. I have looked for a tutorial that I can follow but have had no luck. Thanks.

You first have to install the comport extension as it's not included in the vanilla package. You may be able to find it in the Ubuntu package manager as pd-comport. If not, you could use the deken plugin finder, but that only comes standard in 0.47 and above. So either look for a pd-deken package or follow the instructions here:

https://github.com/pure-data/deken

There's other ways too but that's a start...