Hi! Welcome to the Samsung Members community!
Note: You can't make the battery symbol bigger.
What I suggest is adding a widget to the lock screen with the battery level—easier to see.
For everything else, go to Settings > Home screen > App size. Here you can increase the size of apps.
Screen zoom: Settings > Display > Screen zoom. *fonts
Explore settings- Vision enhancements. A whole bunch to go through and navigate for poor eyesight
You may want to look into the "Magnification" setting


