Your prime issue, other than it being an 11-year old computer, is the hard drive. Its performance scores are excellent, "on the nominals," for that model drive, but it is simple incapable of the speeds newer macOS versions, even High Sierra, and heavy-duty apps (Adobe CS) need.
Were the computer a year newer, the option of swapping out the mechanical hard drive for a solid-state drive (SSD) would be almost life-changing. However the older SATA 3GB drive bus in your computer is a bottleneck that cannot be upgraded. Yes, you would see some improvement but I an not sure if the investment of about US$80-100 is worth it on a computer model going for US$80-100 on the used market.
Even were your RAM not maxed out, more would not change the hard drive issue.
If you wish to pursue the SSD upgrade, which would give you about 4x faster data transfer, please consider only the Curcual MX series or the Electra 3G options from Other World Computing. Those are known-good and Mac-friendly options. OWC has instructional videos on their site so you can seen what is involved. IMHO, most average home users can do the drive upgrade on 2010 Macbook Pros.
One thing that might help with needing a screwdriver: Under CPU usage, "mdworker" —a component of Spotlight—shows it is using 1/4 of your CPU capacity at the time of the test. Run the test again when the computer has NOT been restarted for about 4-6 hours and see if mdworker is still being hoggish.
If it is, consider using system Preferences > Spotlight to limit what Spotlight has to index. Most apps like Mail have built-in search engines so you don't need spotlight to scan for those. I only have it look for files.