Very few workhouse records are online and unfortunately there are quite a few workhouses for which no 'inmate' records survive.
( I found that Ancestry has records from London, Glamorgan, Bedfordshire and Cornwall workhouses (plus every longterm adult inmate in England and Wales in 1861) Find my past has records from Manchester, Cheshire znd Derbyshire. Family Search has Kent records . They may have others. Which isn't much help for Newcastle upon Tyne which I suspect might be the one you're looking for)
Most records are held in the local county archives. If you Look up the entry for the workhouse on
https://www.workhouses.org.uk/menu/ (find it via locagions). it will give you a brief history and an indication of where the records are held and what survives. (the site has lots of adverts but the author has done a huge amount of work over many years. Just be careful that you don't fill in a surname and end up on My heritage )