How to do page transactions

Hello,I'mworkingonasysteminphpandIwouldliketoknowhowIcandoitsothatIcanhavetransitionbetweenpages,typehasregister,changeandreport,howcanIlinkthepagesintheinputforminhtml.

ThisismycodebelowhowcanIdoit.

<section><divclass="circle"></div>
            <div class="thin"></div>
            <p>SISTEMA DE INVENTÁRIO</p> 

            <form  name="register" action="index.php"  method="post">
                    <input type="text" placeholder="Setor" name="setor" >
                    <input type="text" placeholder="Usuário" name="usuario">
                     <input type="text" placeholder="Hd" name="hd" >
                    <input type="text" placeholder="Memória" name="memoria">   
                     <input type="text" placeholder="Processador" name="processador" >
                    <input type="text" placeholder="Cd/Dvd" name="cd">   
                     <input type="text" placeholder="Placa Mãe" name="placam" >
                    <input type="text" placeholder="HostName" name="host">   
                    <input type="text" placeholder="Monitor/Patrimônio/Marca/Modelo" name="monitor">   
                     <input type="text" placeholder="Nobreak/Patrimônio/Marca/" name="nobreak" >
                    <input type="text" placeholder="Placa de Rede" name="placar">  
                    <input type="text" placeholder="Placa de Vídeo" name="placav">                   

                <input type="submit" value="Cadastrar">
                <input type="submit" value="Alterar" >
                <input type="submit" value="Relatório">


            </form>

        </section>

and this is the links of the change and report Projects / reports.php link

How could I do it?