That sounds tough. I know what it feels like to be overwhelmed by a job.
I think treating yourself well- good diet, exercise, enough sleep will help in getting your mind to perform at its best. I do notice the difference when I look after myself better.
Is 'Blue Prism' some kind of course? I guess training the brain to concentrate/recall likely would help. Think we find it easier to do things, the more we do them- building neural pathways and all that.
How do other colleagues cope at your workplace? Do they feel overwhelmed too? Sometimes (most times) I think employers simply put too much on their staff. Maybe it's a case that your workload is actually unreasonable- rather than it being about you being inadequate. It took me years to ask for extra help in one of my jobs when from the start- my boss had actually said to a colleague that it was really a job for two people. Companies exploit people- it's not always that you're not up to the task.
I wish you well. If you feel like a part of you wants to survive, best to pursue it BUT to try and make things easier on yourself. Good luck