You'll need to get in touch with the organisation running that site to see if they offer WMS services as well.

Keep in mind that when you're getting WMS you're just getting an image, so no option to turn specific features on or off (as people pointed out previously), you'll need a WFS for that.

thanks i understood it better

Steps to find services in webviewers:

• Wait till the screen is loaded.
• Press F12.
• Zoom in one level.
• Look for requests in the Network tab.

What I see is:

http://watkipw009.dpaorinp.de:6080/arcgis/rest/services/GEOBASISDATEN/DK_NL_EGG_cached/MapServer/WMTS/tile/1.0.0/GEOBASISDATEN_DK_NL_EGG_cached/default/default028mm/5/6/13" target="_blank">https://danord.gdi-sh.de/viewer/proxy?http://watkipw009.dpaorinp.de:6080/arcgis/rest/services/GEOBASISDATEN/DK_NL_EGG_cached/MapServer/WMTS/tile/1.0.0/GEOBASISDATEN_DK_NL_EGG_cached/default/default028mm/5/6/13

The thing is, the requests have start with "https://danord.gdi-sh.de/viewer/proxy?".  I believe they use a technique to prevent the service being used at another place than this viewer. 

http://watkipw009.dpaorinp.de:6080/arcgis/rest/services/GEOBASISDATEN/DK_NL_EGG_cached/MapServer/WMTS/tile/1.0.0/GEOBASISDATEN_DK_NL_EGG_cached/default/default028mm/5/6/13" target="_blank">https://danord.gdi-sh.de/viewer/proxy?http://watkipw009.dpaorinp.de:6080/arcgis/rest/services/GEOBASISDATEN/DK_NL_EGG_cached/MapServer/WMTS/tile/1.0.0/GEOBASISDATEN_DK_NL_EGG_cached/default/default028mm/5/6/13

thanks for ur suggestion ,which other site offer free access to wms ,topological map that i could use in fme .

Are you looking for a specific region or country?

i am looking for each cities (polygon ) in germany . please,it is important to me to find a soluton to cancel specific color in map .is it hard to extract colors ?

It can be (as was mentioned previously) very hard to extract specific colors out of an image. For the kind of things you want to do I would highly recommend using vector features, such as those coming from a WFS service instead.