I found I also lost motivation at the start of lockdown and working from home.
What helped me was writing out a daily 'plan' which is really detailed about all the things I needed to do each day and then ticking them off. Kind of like a reward chart for adult children!
I had a list of first thing in the morning things which honestly said 'get out of bed' (set alarm for certain time, get out at this time), wash/have shower, dress for the day, take tablets, feed the cat, decide what's for dinner and check you have this, do packed lunches, put on washing machine and so on.
Then the work sections had work related tasks separately, then there was a list 'to buy' at the shops.
I had a list of meals to cook, a list of friends to contact, and a list of occasional jobs (e.g, put out bins)
I checked my diary and this list every day to tell me what to do.
Sounds ridiculous, and I am a grown-adult with two teens, but I found the endlessness of home working to be really awful, I didn't know when my work day started, I didn't bother getting ready and then felt awful, this helped me structure my day. I also took herbal supplements to lift depression and fitted in a little bit of exercise (steps, classes, music) as well.
It really helped me and now I don't dread working from home. I also don't use the lists really as the habits have embedded and I never lie about on a work day.
Hope this helps you, it is not obvious where work ends and your life starts when you are WFH and being alone a lot is mentally difficult for many, so you are not alone.