The Big Four
I am a big advocate of compound movements for my clients as well as my own training as they work multiple muscles and joints in just one exercise. This can simplify your training by making your workouts more focussed and effective. I believe each compound movement falls into one of four categories of push, pull, squat and hinge.
The push category can be further broken down into vertical and horizontal pushing and is typically the overhead press and bench press, but the bodyweight equivalents are the push-up, handstand push-up and the dip. The pull category can also be broken down into vertical and horizontal and includes the pull-up and rowing variations. Squat is the barbell squat, but if working out at home the pistol squat and shrimp squat are good alternatives. The hinge category is typically covered by deadlifts alone, but with limited equipment nordic curls and single leg romanian deadlifts are good options. Although mostly a core focused exercise leg raises also fall into this category due to the hinging motion of the hips.
If you want to get started with a form of resistance training then the big four are a great place to start. They will cover the majority of your upper and lower body to increase strength and keep your workouts balanced. Each exercise can all be scaled downwards to match your current ability and scaled upwards to increase the difficulty so they can keep you busy for a long time.
Here is a full body routine you can use to get you started based around the big four. Take minimal to no rest between exercises and 90 seconds after each round.
Complete for 3-5 rounds:
Bodyweight Rows: 6-12 reps
Push-ups: 6-12 reps
Shrimp Squat: 6-12 reps per side
Leg raises: 6-12 reps