Removing paint & varnish can be quite a dangerous task as the chemicals in some products can be quite dangerous.
I use Home Strip ... made by Ecosolutions
find them on Instagram it is the best & on the market!
Amazon can deliver too!
lots of people use for up cycling furniture & painted woodwork etc.
a completely safe product to use.
I highly recommend HomeStrip & Trade Strip
the secret is to cover the item With plastic to keep it moist.
My (@ToolTalk1) Instagram has a 100 year old surface lock restoration from start to finish using Home Strip