So two years ago I had some stalkers and some seemed to know lots of things about me, so I want to know how can I find out if someone is spying on my laptop(home)and my android mobile phone.
Make sure you do the following checks carefully -
If you are on windows, then try to run System File Checker (Run as administrator >> sfc.exe) Utility to analyze any corrupted data in your system. Do a network analysis check from your system and check for incoming and outgoing packets. Many tools are available for this but I would recommend using WireShark for Windows & Linux and Interceptor for Android Be careful with fake antivirus messages or notifications, this can be a sign of being hacked. IRC clients are another common way for a hacker to get into a computer network. If you have ever participated in an IRC chat, your computer could have been hacked. Backdoor, Trojans, Spyware, Malware etc are sign of getting hacked. Try running a scan through existing tools and remove it. Some of these tools are - SpyBot, HijackThis, ComboFix. There are many other precautionary measures available which will help to be safe on network.
I hope this might help you.
With great difficulty. Once you get to the point of analyzing Wireshark logs, you will spend more time looking at logs than actually doing anything useful on your devices.
Once a clever bit of malware is on your system, you can't trust anything that machine tells you.
Much better to start off with a known good machine, with a fresh install of the operating system (preferably not Windows), and then don't install anything but trusted software from trusted sources. No dodgy hacked games. No software that a pop-up tells you that you need to install (even if it's "recommended").
If you're out-and-about, connected to a public wireless hotspot, then assume somebody else is looking at everything you do. Keep private things to private networks.
Of course, if you regularly post on social media, then everybody already knows everything about you. So they don't need to hack your computers.