There are several methods you can try, but ideally, you’d have to know what is causing the throttling. If throttling is the result of going over your data limits, then reduce your internet use or change internet plans. If it’s because of the type of activity you’re conducting (like streaming or heavy downloading), then a VPN is your best bet. If your ISP is throttling you simply to lower overall congestion on its servers, there is not much you can do about that other than change providers.