Hi and welcome to ECF!
You should stop smoking at your own pace. Many do both, slowly weaning off of cigarettes while
vaping. This works for a lot of people, but others quit just cold. Experiment a little, try to cut back on smoking and instead
vaping. If you feel like you can stop completely in a few days/few weeks/few months, then do it and see if it works out.
Starting slow is probably the best route, but your results may vary.