You are allowed to access to some amount of Dark Web markets using only the urls, what implies a tricky situation : prospective clients and dealers can't join the market before they will acquire an link from an previously enrolled user.
Look at https://darkwebonion.com/, it has fresh URL to suggested Deepweb marketplaces. You should follow these alternative links to register on the sites.
Whenever there are some problems with an access (links don't work), you may lie in wait and check for Deep Web marketplaces alternative URLs. Carry on, as a several amount of the markets close and open signing up periodically, depending on server load.