SALESFORCE with JAVA

hold.tarI have failing call to update a table of salesforce. It returns this message:

update Opportunity set NextStep='Contact John Smith' where ID = '0066g00000fjfOqAAI'[ { "message" : "unexpected token: update", "errorCode" : "MALFORMED_QUERY" } ]


Here is my source code

public class SFEngine {
        public static final String clientId="3MVG9LBJLApeX_PDRFsRBGTuqsN.m3Vd1bIwEF5_FNoEUKGVX0gBqUM1YdL52614KXSW9O6pL6abWun9soVyw";

        public static final String clientSecret="8F418A0BCE45412081ED5D3057A20B178C203A05EC368BFC67D82FF5C4BFBD92";
        public static final String redirectUrl="https://na174.salesforce.com/services/oauth2/callback";
        public static  String tokenUrl="https://login.salesforce.com/services/oauth2/token";
        public static final String environment="https://login.salesforce.com";
        public static final String username="xxxxxxxxxxx";
        public static final String password="xxxxxxxxxxx";                

        public static  String accessToken="";
        public static  String instanceUrl="";
        public HttpClient httpclient;
        public  HttpResponse queryResponse ;
        public  JsonNode queryResults;
        public  HttpGet get;
        public  URIBuilder builder;

private static final String TOKEN_URL =  "https://login.salesforce.com/services/oauth2/token";
public static String  OpenRest(String ID, String Field, String Value) {

        String consumerKey = clientId;
        String consumerSecret = clientSecret;
        String ReturnString = new String();


        try {
            // login
            final CloseableHttpClient httpclient = HttpClients.createDefault();

            final List<NameValuePair> loginParams = new ArrayList<NameValuePair>();
            loginParams.add(new BasicNameValuePair("client_id", consumerKey));
            loginParams.add(new BasicNameValuePair("client_secret", consumerSecret));
            loginParams.add(new BasicNameValuePair("grant_type", "password"));
            loginParams.add(new BasicNameValuePair("username", username));
            loginParams.add(new BasicNameValuePair("password", password));

            final HttpPost post = new HttpPost(TOKEN_URL);
            post.setEntity(new UrlEncodedFormEntity(loginParams));

            final HttpResponse loginResponse = httpclient.execute(post);

            // parse
            final ObjectMapper mapper = new ObjectMapper().enable(SerializationFeature.INDENT_OUTPUT);

            final JsonNode loginResult = mapper.readValue(loginResponse.getEntity().getContent(), JsonNode.class);
            final String accessToken = loginResult.get("access_token").asText();
            final String instanceUrl = loginResult.get("instance_url").asText();


            final URIBuilder builder = new URIBuilder(instanceUrl);
builder.setPath("/services/data/v47.0/query/").setParameter("q", "update Opportunity set "  + Field + "=" + "'" + Value + "'" + " where ID = " +  "'" + ID + "'"  );
ReturnString = new String("update Opportunity set "  + Field + "=" + "'" + Value + "'" + " where ID = " +  "'" + ID + "'"  );

            final HttpGet get = new HttpGet(builder.build());
            get.setHeader("Authorization", "Bearer " + accessToken);

            final HttpResponse queryResponse = httpclient.execute(get);

            final JsonNode queryResults = mapper.readValue(queryResponse.getEntity().getContent(), JsonNode.class);

            System.out.println(mapper.writerWithDefaultPrettyPrinter().writeValueAsString(queryResults));
            ReturnString += mapper.writerWithDefaultPrettyPrinter().writeValueAsString(queryResults);

  }
        catch (Exception e) {
            e.toString();
            e.printStackTrace();
        }
      return ReturnString;
    }



 } //end of class


/////////// same query works for a select statement
 builder.setPath("/services/data/v47.0/query/").setParameter("q", "SELECT ID, Name, Description, LeadSource, Type, Amount, Probability, LastViewedDate, CloseDate, ExpectedRevenue, LastActivityDate, IsWon, NextStep  FROM opportunity where ID = " + "'" + ID + "'");


returns:
{ "totalSize" : 1, "done" : true, "records" : [ { "attributes" : { "type" : "Opportunity", "url" : "/services/data/v47.0/sobjects/Opportunity/0066g00000fjfOqAAI" }, "Id" : "0066g00000fjfOqAAI", "Name" : "AWSWaveLength.COM", "Description" : "AWS Experts is designing EDGE servers. This information will also be in SERVICENOW as a KB article once this is completed and closed.", "LeadSource" : "Partner Referral", "Type" : "New Customer", "Amount" : 800000.0, "Probability" : 85.0, "LastViewedDate" : "2020-01-23T19:01:40.000+0000", "CloseDate" : "2020-03-31", "ExpectedRevenue" : 680000.0, "LastActivityDate" : null, "IsWon" : false, "NextStep" : "WINTEMPLATES" } ] }


 
YOU CAN TEST these with these RESTAPI calls
select
http://ec2-18-217-26-94.us-east-2.compute.amazonaws.com:8080/VZServiceNowHub/Server/SFOpportunity/0066g00000fjfOqAAI 

update

 http://ec2-18-217-26-94.us-east-2.compute.amazonaws.com:8080/VZServiceNowHub/Server/SFOpportunityEdit/0066g00000fjfOqAAI/NextStep/Contact John Smith