Gyms are opening up again after a long break. Hopefully during that break you were doing some kind of activity to stay moving. If you were you are ahead of some of us who weren't. Now that you are back in the gym its this is the time to remember to take it slow. Studies show after 3-4 weeks of not lifting you lose 25% of your strength, you lose cardiovascular capacity faster usually a few day.
Now that you are back in the gym take it slow. First foam roll. It gets blood flowing to the body and loosens up any restrictions in the body that will prevent proper form. Next core activation, that includes the TVA (transverse abdominal muscle), Obliques, and thoracolumbar region. FInally less weight and more reps would be idea for a few weeks to let your muscles get use to being under a load. Doing too much to fast increases possibility for injuries. Take it slow and grow