My daughter started at 16 months and now aged 2 and a bit can scoot about 400m down a hill with feet up. She doesn’t get pedalling though and at the moment we’re happy with her just scooting!
No bragging here!
I have 4 kids and my eldest rode a bike aged 5 after a lot of tears and crashing and stabilisers. My second eldest rode at 4 after 15minutes of trying off the back of a balance bike since age 3. Second youngest (well see above!!!) 4th is just walking and will not be on for a while!
I would just leave it lying around and see if they show interest. IME some do, some don’t. i gave my neighbours lots of advice re: scoot bikes but their son hates it and won’t try, though he does like walking alongside and pushing! I think that’s a start and reckon he’ll see someone else one day and try.
Don’t rush!