Link Table A Column NAME with Table B data MSSQL Server

I am trying to link(join) the NAME column from PBXSTATION to the PBXDATA table. I also want it to be able to match the NAME with the EXT(extension) column? EXTENSION in PBXSTATION is the same as EXT in PBXDATA. I will rename EXT to EXTENSION, that way the fields match. Any help would be great. My MSSQL Server is a little hazy. Thank you!