The most likely reason your system is running slowly is a problem with your Internet connection.  The first thing to do is run a speed test to determine if the problem is the connection.  Google “speed test” for an assortment of online services that will calculate your download and upload speeds (e.g. http://speedtest.net or similar).  If the speed test results are good, then the problem may be internal to your computer or device. There may be software running in the background (e.g. updates, backups, virus scans, etc.) that is interfering with your Internet connection which, in turn, makes your Internet experience appear to be slow.