Image of partially stripped step below.
I'm very new to DIY so apologies in advance for any silly question.
I am using a heatgun (350c) and ffp3 cheap mask (£5). I plan on painting over once stripped. The step (for example central section back) has very tricky to strip small parts of paint, , is it worth leaving this and just sanding over? There is also material on the left and right sections of the step that is very hard to remove, not sure if paint or glue or anything tbh. Also worried it may be lead paint, are the "safety precautions" I've taken above sufficient?
Final question - does anyone have any idea what kind of wood it is?