Click on  the Text icon in the toolbar to the left of the page on the screen.

Then click anywhere on the image on which you want text to appear.

You can choose your own Font Name  (see 1 above) and Size (see 2 above)

Choose the Font Colour by clicking on the colour block at 3 (see image below for more details)

Make sure Vector is selected (see 4 above).

You can also choose the normal Font Attributes (see 5 above)

Moving, text

Move the mouse pointer over the text, but towards the left. Click and drag when the 4 arrows appear (as above).

resizing text

Move the mouse pointer over the text, but towards the corners. Click and drag when the 4 diagonal arrows appear (as above).

rotating text

Move the mouse pointer over the text, but towards the right. Click an drag when the curved arrows appear (as above).