@mariajo Split squats but also elevate your front foot, this allows for more ROM as your back knee can really get down there. These are KILLER, I've been lifting for over 10 years and doing these with solid form with 40lbs will kill me.
Another is Ham curls on an exercise ball. These are radically underrated IMO. Keeping your butt upp the whole time keeps isometric tension on the hams from the hip, then the curl contracts from the knee. Again, done with correct form a set of 12 will liquidate hams.
Also you could set up belt squats with a barbell like this.
I did this for about a year before making a more specific lever out of some 2x4s but this will get the job done.
You can also get cheap belt squat attachtments like this one for around $70
I feel you as another Homegym enthusiast with minimal equipment hitting legs can be hard!!!