I was an only child, widowed mother who worked full-time (shifts). She was a wonderful loving mother but I don't remember her ever PLAYING with me. My Nan lived with us and she would tell me wonderful stories out of her own head.
Mostly tho I entertained myself:
read voraciously (early reader taught by mother, pointing at words as she read aloud)
climbed trees in the garden
picked out simple tunes on our old piano, sadly this was sold before I became a Kanneh-Mason, although I could do a good Old Macdonald by the time it left us
Played games with myself (I had a toy roulette wheel which amused me a great deal, I even worked out a foolproof system to 'always win in the end' - turned out to be a well known, and completely discredited, idea😝
Used my Spirograph a LOT
Loved Lego, but it was expensive so had to invent my own designs mostly from a big box of bricks, rather than kits with blueprints
Lined up my Matchbox cars (spend my pocket-money on these, I think they were 2 shillings each)
After 10 or so I had a great friend who lived nearby and we amused one another, often out of the house.
I am making a huge, concerted effort NOT to buy my little grandson too many toys (have failed a bit, of course😔) but a truck full of bricks, a playpen with balls in it, baby board books, a Little Tikes rocker, a frame he climbs up, and a baby 'bike' (with help) have all been hits. I did buy a couple of V-Tech things with sounds and lights, but these don't keep his attention half as long as the simple wooden bricks.
I've also given him a basket of 'safe crap' from the kitchen for him to explore and think about while sitting beside him on the floor in case he wants to show me something. I seldom interfere if he's content.
I'm not daft, I know this will change!. (He is already showing an alarming interest in our phones and will always dive for one if he spots someone holding one!) but I'd love him to be resilient in finding his own amusement and entertainment in things!