Starting a renovation
Welcome to the forum!
Not sure what you're looking for in proper procedures, but typically:
1. Have design drawings prepared specifying the work to be performed
2. Have builders submit bids based upon your drawings
3. Select a qualified builder and sign a contract
4. have builder apply for building permits
4. be prepared to have your normal routine disrupted while construction is performed
as far as the beam, the size and type of beam is based upon the total loads it must support and the physical constraints of where the beam must go (length, width, height). it may be dimensional lumber, structural composite lumber (glulam, PSL, LVL) or metal (steel or aluminum).
"You get what you pay for, and sometimes free costs more!"