Don’t rush it
Each bank will have different loan approval processes. Provide all the information the bank needs upfront so they have a good understanding of why you need the loan.
The first bank officer or loan specialist you talk to may not be the person who makes the final decision on your loan. It depends on the size of the loan you want, the size of the bank and the systems the bank has in place for loan approvals.
You are certainly entitled to ask how long the process might take, but avoid placing any pressure on the bank to respond as this will not hasten the process.