Depends on a lot of things. Are you pre approved and do you have solid credit?
Are you working with an agent?
If you are paying cash generally the soonest this can happen is about a month.
Generally in a perfect world when an offer is accepted and things happen it takes 35-90 days until settlement .
Even in a perfect 'offer' world you may have home inspections, appraisers, and the Use and Occupancy to deal with (all can cause a small or large or no delay). Title search etc.