Well I had that problem too and i know how it feels, but what i did was: some push ups (if you see it too easy try to do some burpees), then 10 seconds of plank (the next day kinda more), and by last some running in my place… but also if you feel to grumpy to do all theses, you can only do the first one, you don't have to preasure yourself
It is going to sound weird but you should try out dancing. Just play some music for 5-10 mins and let yourself get driven by the songs. Do it alone preferably so that you can truly let yourself go, but if you have a partner that doesn’t judge you, you could do it with them too.
I usually practice yoga, I find it relaxing and it does help me with anxiety, I don't practice it everyday, but I do practice it around six times a week, it helps with motivation also, so I fondly recommend it.
Just do some push-ups! You can start with one and then add one every day or just when you feel like it. Eventually you’ll be able to do 10 push-ups or even 20, 30, 50, 100! That’s gonna be a great motivation to start working on other exercises too. You’re welcome!