You will need some skills to create a SVG image by writing a path source code. This way of SVG image creation is quite difficult.
To convert PNG image to SVG image, you can use some free online tools, for example
Convertio.co.
Because of the differences between PNG and SVG image format, the conversion may be not always the best.
SVG is a web-friendly vector image format, while PNG is a raster image format.