This depends on the cause of the issue. Firstly, contact your current provider for the speeds you should be getting. Next, confirm that you are getting these speeds by running a speed test. Compare your results and assess whether it's an internal issue or a provider issue.
If it is an internal Wi-Fi issue, changing providers may not resolve the issue. If they cannot provide you with speeds to suit your needs, switching to a new supplier for a faster broadband plan can help.
If the issues occur while directly connected to your router, this is more likely a router issue or internet provider issue. Contact the technical support of your provider to see if they can be of assistance. If they are unable to offer you support, look for an alternative provider.