My phone is infinix smart 5 and it does't support 4G and 5G network.

Looking up your phones specs we can see it came out in 2020 and offers the following bands

Technology GSM / HSPA / LTE

2G bands GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2

3G bands HSDPA 850 / 900 / 2100

4G bands 1, 3, 5, 7, 8, 20, 38, 40, 41

Speeds HSPA 21.1/5.76 Mbps, LTE Cat4 150/50 Mbps

So you have a workable 4G phone but you do need to register your phone with the local service provider. And of course the providers cellular network needs to be a accessible. Depending on your location the nearest cell tower maybe blocked or is of a different provider than you have registered to.