I would like to extend wifi coverage in my home by connecting a deco m5 to my existing tp-link archer c9 ac1900 wifi router wirelessly. Is this possible?

I only own one m5 deco and I would like to use the it as an access point and place it in another part of the home to have seamless wifi coverage.

Does my one deco m5 need to be connected to my exsting tp-link c9 router by ethernet cord?

Will I have to buy another deco m5 to place in another location in my home?

Please help.