Discaimer: This is what I would do with that computer, not what is necessarily the right thing for OP.
Assuming you running Windows on that hardware, my guess is you either run W7 (terrible choice because no loger being maintained) or you've upgraded to W10 that amongst other installed things are huge resource hogs and not being an ideal choice.
Therefore I'd toss out Windows (remember always backup of personal files to an external hdd) and test alternatives OS systems that is less demanding for the hardware. Here I can suggest
Linux Mint xfce/Mate, or
Linux Lite - those are just the first ones that pops up in my head because the desktop and concept of a start menu that is somewhat similar to Windows 7.
The boot mediums for most Linux distributions are made so that it can be tested (called
Live Desktop) without being installed. This way, you have a chance to test out how the system looks and feel, and can play around without breaking the existing OS.
The only downside for a regular user is that Linux is a complete different OS compared to Windows. What you're used to in Windows may not apply in a different OS, especially when it comes to installing software, what software is available, amongst many other things. It is doable, but require patience and spending time to learn new concepts.
True to be told - this can be an overwhelming experience especially if that is the only computer you have access to.
However - I think realistically there are the following choices:
- Continue using it like this with no change. Probably not a god idea in the long run.
- Installing Linux. Pick a distribution mentioned above and just take the plunge. Before this, you must get an idea if there are some software packages you for some reason just cannot live without (this use to be MS Office, Adobe programs, etc).
- Just purchase a new laptop, the old one can be given away (afer cleaning of any personal stuff, software licenses etc - just wipe everything from the hdd).
- Re-install existing OS (if it is W10). If you have a valid license, it should run to 2025 (I think it was before MS stop providing updates and it being unsafe).
No matter what choice you take, use a external hdd or a large usb stick to backup any personal files from that computer.