Do you have an Order Table and a Company Table (with your customers' details)?
You can create a relationship between the Order Table and The Company Table, using the identifier Company Name as the match field. Then in the Order Layout you can set the fields of address, phone, etc from that relationship.
If you get that to work it will show you the principle. But it is not good practice to use 'Names' as a match field. You should really give each Company Record a unique ID Number, and use that to match with - even though the user only ever sees the Company Name.
There is more than one way to get data from a related table to appear when you select your value. (And as Sorbsbuster recommends, it should be an ID number that links the two records, not the name field.)
Here's a link that describes the two basic approach. Which is best for your system depends on how you need to use this data: Auto Fill