I’m going to assume for whatever reason you have no gym access, no squat rack and no bench but you may have some adjustable dumbbells and a barbell with plates. You can still get fit and strong without it. However, if you want to get into powerlifting I recommend investing into both of these things when you can. Some people may not have dumbbells or barbells — for those people I strongly suggest they make sandbags which I discuss at the end.
1. Replacements for Squat
If you have dumbbells you can do these movements for legs: Dumbbell Step Ups, Dumbbell Lunges, and Dumbbell Squats. The movements for dumbbells can work for kettlebells as well.
If you have a barbell you can do: Barbell Hack Squat (which is a reverse deadlift), Clean & Squat (basically pick it off the floor and do a front squat), and take the plates in your hands and do the same movements as the dumbbell movements for legs. You can also make sandbags and do clean and squat and lunges if you have no barbell or dumbbells.
Bodyweight squats and hill sprints will also build those quads. Bodyweight squats done for very high reps 500-1000 total reps will grow your quads. I’ve experienced it myself.
2. Replacements for Bench
You can do a floor press (which is basically a bench press just done laying on the floor) with dumbbells, kettlebells, sandbags and barbells. You can also do flyes for extra chest work. You can also do dips and push ups. You can still have a spotter for the barbell floor press although it can get a bit awkward as your partner needs to basically deadlift the bar for you. I’m going to recommend leaving 2-3 reps in the tank and not going to failure.
If you have no barbell to deadlift with you can still do them with kettlebells and dumbbells. You can even do zercher deadlifts with the sandbag.
A problem may present itself where you are getting too strong on the deadlift and you cannot afford or get more plates right now. You can start doing them one armed. Either from the front or from the side suitcase style. You can also do them one legged one armed with dumbbells and kettlebells.
There isn’t many good substitutes for deadlifts but you can try power cleans as well.
Suitcase style one arm deadlift
One arm conventional deadlift
If you only have your own bodyweight then hill sprints, glute ham raises, reverse hypertensions and bridges are your best bet for hamstrings and back.
4. Making Equipment
You’ll need duct tape, a shovel, sand or dirt, an old duffel bag and garbage bags. Fill the garbage bag with dirt and duct tape it. Make it heavy or light whatever you want. Put it in the old duffel bag. Now you can make it heavy or light as you want. An adjustable sandbag. If you really cannot go dig then go to the hardware store get a bag of quick dry cement or gravel etc.
b) Chin up bar
If you can’t install one or make one you can try using your door frame but it may break. Pipes may break as well. A tree outside may be good. Monkey bars at a playground (be careful there though ha). My home chin up bar is a piece of PVC pipe screwed into my basement ceiling.
c) Dip bars
Again you can use your imagination for this. Sometimes even two shelves close together can be used for dips. It’s not too hard to make and I’ve seen dip stations sell for quite cheap.
d) Weight/dip belt or weighted vest
If you don’t have them or can’t get them. Take a sturdy backpack and fill it with stuff. You can use your bathroom scales to see how heavy it is. Viola. You can also use it to do weighted dips and push ups. If you have plates or dumbbells you can put them in. You can also hook your feet onto a dumbbell or kettlebell so you can hold it up as you do your chins.