SpringBoot报错：Error resolving template [index], template might not exist or might not be accessible by any of the configured Template Resolvers

springboot项目正常启动，但是在访问页面的时候报错，错误信息如下：

Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Wed Mar 29 13:52:03 CST 2023

There was an unexpected error (type=Internal Server Error, status=500).

Error resolving template [index], template might not exist or might not be accessible by any of the configured Template Resolvers

org.thymeleaf.exceptions.TemplateInputException: Error resolving template [index], template might not exist or might not be accessible by any of the configured Template Resolvers

at org.thymeleaf.engine.TemplateManager.resolveTemplate(TemplateManager.java:869)

at org.thymeleaf.engine.TemplateManager.parseAndProcess(TemplateManager.java:607)

at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1098)

at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1072)

at org.thymeleaf.spring5.view.ThymeleafView.renderFragment(ThymeleafView.java:362)

at org.thymeleaf.spring5.view.ThymeleafView.render(ThymeleafView.java:189)

at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1373)

at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1118)

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1057)

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)

at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:626)

at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:733)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:542)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:143)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)

at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:374)

at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)

at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:888)

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1597)

at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)

at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)

at java.lang.Thread.run(Thread.java:748)