That's not much information to go on. Has anything changed, or has it always been like this?
From what I've been able to find about it this is an extremely basic tablet, with 1 GB of RAM and one of the lowest-powered processors I've seen for a long time (the Cortex A7 core is a 2011 design, and benchmark scores I've found for this tablet are actually similar to those of a 2011 flagship phone). So if it's trying to run a recent version of Android (I've seen 7,.1 listed in several posts about this device) I'm afraid it probably is going to be slow no matter what you do.