The IP suite is not nearly as neatly layered as OSI was and the OSI model doesn't neatly fit the IP suite since it wasn't actually designed for IP at all. In the IP suite layers 5 and 6 basically don't exist in the OSI sense, TCP handles things that are part of both layers 4 and 5 in the model despite being a single protocol, etc. The OSI model is often considered obselete as it just doesn't actually fit the IP world all that well but it's been around so long and does have uses in certain situations that it tends to stick around.

ISO/OSI is a neatly separated model mostly used on theory.

In practice, actual network stacks are often modeled after a simpler model that is called TCP/IP. Which despite the name is not actually TCP specific.

Here's the general description and correspondence to ISO/OSI:

1. Host to network / network access layer: it's mostly the nic and nic driver. It's sometimes numbered as 0 because some don't consider it part of the TCP/IP stack, but simply the nic driver. Corresponds to:
   1. Physical
   2. Datalink
2. Network layer: Corresponds to: 3. Network
3. Transport layer: Corresponds to: 4. Transport
4. Application layer: everything that's part of the application and not the network stack. Corresponds to: 5. Session 6. Presentation 7. Application

Or, you can just not care about how the actual software stack is separated, and continue to use the most complete model, knowing that everyone will understand what you when you say "layer 2/3/4" anyway.

Plus, some could say that the TCP/IP model is equally unfit because the Linux network subsystem doesn't care about layers.

Edit: I hope the formatting of that table isn't broken on your client, because it is on mine

ISO is a theoretical model on how things work, suitable for teaching and for reference. In reality, there are only 4 layers and not the finely chiseled concern-separating layers at the bottom.

Nobody responding to you understands that this is a joke, which kinda boggles the mind

IP is the internet layer which is layer 2 and TCP is the transport layer which is layer 3.

Why split physical and data link when they are so closely related? You can't use vpi/vci on an ethernet port, you can't use MAC addresses on a frame relay port. Bundle that shit together.

Presentation, application, and session are all dealt with by the application anyway so why bother splitting them out from a network point of view?

TCP/IP is also the name of a model different from OSI. It has 4 layers instead of 7: https://www.hostwinds.com/blog/osi-vs-tcpip-differences-and-similarities

How don't they fit?