A1 mechanic question will there always be 2 tensions on eg a string pulling a mass t

will there always be 2 tensions on eg a string pulling a mass tension up and below?

Why is there 2 forces of tension? Should there only be one and the one pulling the mass

Why is there 2 forces of tension one up and one down, shouldn’t there only one pulling the mass

Will there always be 2 tensions? In this example they found the tension going up, will the tension going down be the same ?

As per the previous post, the "two" tensions are equal and opposite. If you consider P, then Q is dragging P through the tension. If you consider Q, then P is pulling Q through the tension. If you add the equations of motion together, you get the motion of the composite system PQ with no tension being represented.

Can you make it a bit easier to read pls ... orientation, size, which part ...

If its a "normal" string, under tension then yes. Newton 3 basically applies.
https://physics.stackexchange.com/questions/395340/tension-and-newtons-third-law
(probably better examples if you google).

still a bit confused, a the string if facing down the tension is the reason why it still up, wouldn't there be a equal and opposite force on the string so it pushs the masses equally down

diagram in the book

You are getting mixed up about the objects that the forces are acting on.

First make sure you understand Tension. The best explanations I found were here:

https://physics.stackexchange.com/a/307840/182137
https://physics.stackexchange.com/a/340573/182137

If that still does not make sense, some people describe Tension as a bit like a "3D pressure":
https://physics.stackexchange.com/a/567808/182137

If you can kind of get your head around that, then you need to follow mqb2766's advice and then think about Newton's 3rd laws.

Have a look at this first diagram:

From here:
https://deutsch.physics.ucsc.edu/6A/book/forces/node7.html

First you need to consider the forces acting on the mass. This is labelled in red on the diagram. There will be the force due to gravity which goes down (directed towards the centre of the Earth). This is labelled $\mathrm{W}$. Now the mass is applying a downwards force on the rope. By Newton's Third Law, we therefore have an equal but opposite upward force, labelled $\mathrm{F}_{\mathrm{SW}}$ applied on the mass.

Now consider the forces acting on the rope. This is labelled in blue. The rope is under tension due to the mass. So at the bottom, there is a force acting on the rope which goes downwards, labelled $\mathrm{F}_{\mathrm{WS}}$. At the top of the rope the hand (or it could be a pulley), is applying a force upwards to prevent the rope from simply falling to the floor. This is labelled $\mathrm{F}_{\mathrm{HS}}$.

Now consider the force acting ON the hand (pulley). The hand (pulley) is applying an upwards force ON the string. So the string applies an equal but opposite force on the pulley. It applies a force ON the pulley which acts down. This is labelled in green as $\mathrm{F}_{\mathrm{SH}}$.

Unfortunately, a lot of diagrams do not often show the forces in blue (acting ON the rope). They only show the forces in red and green, i.e. the forces acting on the mass and the hand (pulley) respectively. This is fine because there is an assumption that the force throughout the rope is uniform but the side effect is that it leads to the confusion that you have.

You are getting mixed up about the objects that the forces are acting on.

First make sure you understand Tension. The best explanations I found were here:

https://physics.stackexchange.com/a/307840/182137
https://physics.stackexchange.com/a/340573/182137

If that still does not make sense, some people describe Tension as a bit like a "3D pressure":
https://physics.stackexchange.com/a/567808/182137

If you can kind of get your head around that, then you need to follow mqb2766's advice and then think about Newton's 3rd laws.

Have a look at this first diagram:

From here:
https://deutsch.physics.ucsc.edu/6A/book/forces/node7.html

First you need to consider the forces acting on the mass. This is labelled in red on the diagram. There will be the force due to gravity which goes down (directed towards the centre of the Earth). This is labelled $\mathrm{W}$. Now the mass is applying a downwards force on the rope. By Newton's Third Law, we therefore have an equal but opposite upward force, labelled $\mathrm{F}_{\mathrm{SW}}$ applied on the mass.

Now consider the forces acting on the rope. This is labelled in blue. The rope is under tension due to the mass. So at the bottom, there is a force acting on the rope which goes downwards, labelled $\mathrm{F}_{\mathrm{WS}}$. At the top of the rope the hand (or it could be a pulley), is applying a force upwards to prevent the rope from simply falling to the floor. This is labelled $\mathrm{F}_{\mathrm{HS}}$.

Now consider the force acting ON the hand (pulley). The hand (pulley) is applying an upwards force ON the string. So the string applies an equal but opposite force on the pulley. It applies a force ON the pulley which acts down. This is labelled in green as $\mathrm{F}_{\mathrm{SH}}$.

Unfortunately, a lot of diagrams do not often show the forces in blue (acting ON the rope). They only show the forces in red and green, i.e. the forces acting on the mass and the hand (pulley) respectively. This is fine because there is an assumption that the force throughout the rope is uniform but the side effect is that it leads to the confusion that you have.