Dear @Med.EL,

Switche2 and 3 are a TL-SG1016 whereas Switch1 is a TL-SG1024 I don't know if VLAN is necessary to achieve such topology on these unmanaged switches

1. Unmanaged switches doesn't support VLAN. In fact, the unmanaged switch doesn’t support any configuration interface or options. 

2. To achieve such topology, you need Easy Smart/Smart/Managed switches, please read the following configuration example for details.

How to configure 802.1Q VLAN: https://www.tp-link.com/support/faq/788/

I would like to know if there is any possibility to increase bandwidth by trunking 4 Ethernet cable between each switch

To achieve this, the switch needs to support Link Aggregation Group (LAG). Please kindly check for the following configuration guide.

Configuration guide for LAG

How to configure 802.1Q VLAN for LAG ports: https://www.tp-link.com/support/faq/2396/

Hope the above information is helpful.